Britannica Student Encyclopedia - 2010

people work in agriculture, manufacturing,

and trade. Many farmers raise sugarcane,

soybeans, sheep, and cattle.

History

People have lived in what is now Bolivia

for thousands of years. An advanced

people lived in the area around Lake

Titicaca (in western Bolivia) about

1,000 years ago. The region was later

part of the powerful Inca Empire.

The Spanish conquered the area in the

early 1500s. They ruled Bolivia as part

of a larger region that included what is

now Peru. Silver mines brought great

wealth to the region. By the end of the

1700s, however, there was little silver

left. The Bolivians won their

independence from Spain in 1825.

They named the new republic after

Simon Bolivar, who helped free the

region from Spain.

After gaining independence, Bolivia

fought several battles with neighboring

countries. In the War of the Pacific,

from 1879 to 1883, Bolivia lost

territory along the Pacific Ocean to

Chile. In the Chaco War, from 1932 to

1935, Bolivia lost most of the Chaco

region to Paraguay. Bolivia also had

trouble forming a stable government.

The military ruled several times during

the 1900s. But in 2005 the country

elected its first Indian president. He

promised to give the Indians of Bolivia

a greater voice in the country’s affairs.

..More to explore

Andes • Bolivar, Simon • Inca • La Paz

• Sucre

Llamas stand on the shore of a lake in southwestern Bolivia.

Facts About

BOLIVIA

Population

(2008 estimate)

9,694,000

Area

424,164 sq mi

(1,098,581 sq

km)

Capitals

La Paz (administrative)

and Sucre

(judicial)

Form of

government

Republic

Major cities

Santa Cruz, La

Paz, El Alto,

Cochabamba

BRITANNICA STUDENT ENCYCLOPEDIA Bolivia 103

Bomb

Bombs are weapons that people use to

kill others and to damage property.

Bombs are designed to explode. They

may be dropped from aircraft, delivered

by rockets, thrown by hand, or placed

next to a target and blown up later.

Parts of a Bomb

A bomb is basically a container filled

with explosive material. This material is

usually a mixture of chemicals. A part

called a fuse ignites (sets on fire) the

explosive material. There are several

types of fuses. Some fuses cause the

bomb to blow up when it hits something.

Other fuses cause the bomb to

explode after a certain amount of time.

Bombs that fly through the air have fins

or wings to keep them steady. Some

bombs, called smart bombs, have a system

that allows people to guide them in

flight from far away.

Types of Bombs

Armies and other military forces use

several types of bombs. Demolition

bombs destroy buildings with a powerful

blast. Fragmentation bombs explode

into small, fast-moving metal fragments

that are meant to kill people. Generalpurpose

bombs combine demolition and

fragmentation. Armor-piercing bombs

are heavy and pointed. Armies use them

against protected targets. Incendiary

bombs cause intensely hot fires. Cluster

bombs contain many small bombs, or

bomblets.

Criminals and terrorists sometimes

make and use their own bombs. These

bombs may be simpler than the bombs

used by armies, but they can be very

destructive. They include car bombs,

pipe bombs, and letter bombs.

Nuclear bombs are the most powerful

bombs of all. There are two types of

nuclear bombs: atom and thermonuclear

(or hydrogen). They both get their tremendous

force from reactions that take

place in the nuclei, or centers, of atoms.

(Atoms are the tiny building blocks of

everything.) The energy released by a

nuclear bomb destroys nearly everything

for miles around.

History

Grenades were the earliest bombs. These

are small devices that are thrown by

hand. Soldiers first began using grenades

in about the 1400s. Eventually other,

more accurate weapons were developed.

But grenades are still used today.

A U.S. Air Force plane drops bombs during

an attack on Afghanistan in 2001.

104 Bomb BRITANNICA STUDENT ENCYCLOPEDIA

After airplanes were invented in the

early 1900s armies started using them

to drop bombs. During World War I

(1914–18) bomber planes could not

carry many bombs at one time. By

World War II (1939–45), however, that

changed. Airplanes were able to carry

larger bombs in much greater numbers.

The first nuclear bombs were developed

during World War II. The war ended

shortly after the United States dropped

atom bombs on two Japanese cities,

Hiroshima and Nagasaki, in August

1945. The bombs caused immense

devastation. They killed more than

100,000 people. The United States

tested the first hydrogen bomb in

November 1952. It was even more

powerful than the atom bomb. Several

other countries later developed nuclear

bombs of their own.

In the 1980s and 1990s many people

were afraid that other countries would

use nuclear weapons. Leaders of the

countries that had such weapons began

to talk about ways to control the

weapons. They agreed to limit the

production, testing, and use of nuclear

weapons. In 1996 representatives from

approximately 60 countries signed an

agreement to stop all testing. The

agreement was called the United

Nations Comprehensive Test-Ban

Treaty.

In wars today armies still use traditional

types of bombs. However, new inventions

have made it easier to deliver them

with greater accuracy. Armies therefore

do not use as many bombs as they once

did.

#More to explore

Army • Nuclear Energy • Rocket

Bombay

#see Mumbai.

Bonaparte,

Napoleon

#see Napoleon.

Bone

Humans and many other animals have a

skeletal system made up of hard pieces

called bones. Bones help to support the

body and to protect its organs. Bones

store important nutrients and minerals,

too. Bones also make blood cells. The

human body has more than 200 bones.

A huge cloud forms after a test of an atom

bomb. The bomb causes so much damage

that it has been used only twice.

BRITANNICA STUDENT ENCYCLOPEDIA Bone 105

Bone Structure

There are two basic types of bone: compact

bone and spongy bone. Both types

are made of calcium and other minerals,

fibers of protein, and water.

Compact bone is solid and very hard. It

makes up the outer layer of all bones. It

also makes up the shaft, or long tube, of

arm and leg bones.

Spongy bone lies beneath most compact

bone. It looks like a honeycomb or a

sponge, but it is not soft. The many

spaces within spongy bone let it absorb

shock, or sudden pressure on the bone.

Bone marrow fills the hollow spaces in

spongy bone. It also fills the hollow

tubes of long bones. Marrow is a soft,

jellylike substance that can be red or

yellow. Red marrow makes blood cells.

Yellow marrow stores fats.

A thin membrane, or skin, covers each

bone. The membrane contains nerves

and blood vessels that are attached to the

bone. The blood vessels carry nutrients

to the bone. They also carry blood cells

from the bone to the rest of the body.

How Bone Is Made

Special cells start making new bone by

building a structure of protein. Blood

then brings in calcium, which sticks to

the structure. When the calcium hardens,

the new bone is complete. The

body can also rebuild bone that wears

away or breaks.

Broken Bones

When bones break, the injury is called a

fracture. Most fractures are simple,

which means they are beneath the skin.

If the bone pokes out of the skin, it is

called a compound fracture. How

quickly the bone heals depends on the

patient’s age. As people get older it takes

longer for broken bones to heal.

#More to explore

Blood • Mineral • Skeletal System

An inside view of an arm bone shows that it

is made of two different types of bone. The

outside edges are compact bone, and the

inside part is spongy bone.

A broken bone is considered a simple fracture

if it stays beneath the skin. It is a compound

fracture if it breaks through the skin.

106 Bone BRITANNICA STUDENT ENCYCLOPEDIA

Bonn

Population

(2006 estimate)

312,818

Bonn is a city in Germany, a country of

central Europe. Germany was divided

into two countries from 1949 to 1990.

During that period Bonn was the capital

ofWest Germany. The city is famous as

the birthplace of the composer Ludwig

van Beethoven. It also has many beautiful

parks. Bonn lies along the Rhine

River.

Many people in Bonn work in government

offices or for the University of

Bonn. The city is also a transportation

center. Bonn has few factories.

Bonn began as a village more than

2,000 years ago. The Romans later

settled the site. They lost control of the

area in about the 400s. Bonn survived

as in independent village for many

years. Later it was the capital of local

rulers. In the 1800s it became a city in

Germany.

The city was damaged by bombs during

WorldWar II (1939–45). After the war

Bonn became the capital ofWest Germany.

West and East Germany were

combined in 1990. Berlin then became

Germany’s capital. But some government

offices remained in Bonn.

..More to explore

Germany

Bonobo

The bonobo, along with the chimpanzee,

is the closest living relative to

humans. It is an ape related to the gorilla

and the orangutan, as well as the chimpanzee.

All these animals are called great

apes because they are large and very

intelligent. Bonobos and other great

apes belong to the larger group of mammals

called the primates. The primates

also include other apes, humans, and

monkeys.

Bonobos can be found in only one area

of the world. They live in rain forests in

the Democratic Republic of the Congo,

a country in Africa. They are highly

endangered, or at risk of dying out completely.

Humans have hunted them and

destroyed much of their habitat.

A statue in Bonn honors Ludwig van

Beethoven. The composer was born in the

city.

Scientists once

thought that

bonobos were

a type of

chimpanzee.

In 1933 they

decided the

two were

separate

species.

BRITANNICA STUDENT ENCYCLOPEDIA Bonobo 107

Bonobos look very similar to

chimpanzees. They have black hair.

Adult male bonobos are larger than the

females. Adult males may be almost 4

feet (1.2 meters) tall. They may weigh

as much as 134 pounds (61 kilograms).

Bonobos do not have a tail, but they

have a tuft of white fur where a tail

would be.

Bonobos eat mostly fruits. Sometimes

they eat leaves and seeds. In rare cases

bonobos will also eat small animals, such

as bats. They spend the day feeding in

trees, resting, and traveling on the

ground to other trees. They also can

swing from tree branch to tree branch

with their arms. Bonobos build leafy

beds in trees to sleep in at night.

#More to explore

Ape • Chimpanzee • Endangered Species

• Primate

Book and

Bookmaking

A book is a printed work that is meant

to communicate. To communicate is to

share ideas or information. A book is

made up of pages that are usually

enclosed in a protective cover. People

have written books about all kinds of

subjects. Among the countless types of

books are novels, picture books, cookbooks,

how-to books, poetry books, and

textbooks.

From Manuscript to Pages

The first step in creating a book is for an

author to write a manuscript. A manuscript

is a book before it has been published.

The author finds a publisher, or a

company that makes and sells books.

Editors at the publishing company help

the author improve the manuscript.

They make sure that the ideas are complete,

that the writing is clear, and that

there are no errors.

Then the manuscript goes to a designer.

This person arranges the text and pic-

Bonobos live in rain forests. They

often feed and even sleep in the

trees.

A bookshop in Italy displays many different

books in its windows.

108 Book and Bookmaking BRITANNICA STUDENT ENCYCLOPEDIA

tures on the pages so that the book looks

nice and is easy to read. A designer also

creates the cover.

Editors and designers continue working

on the pages until they are perfect. Most

of this work is done on computers. The

designed book is stored in computer

files.

Printing Books

Next, the computer files are used to create

printing plates. Printing plates are

sheets of metal or plastic that have the

book’s text and pictures on them. Printing

plates are put on printing presses

and used to print the book.

Most book pages are printed on long

rolls of paper. After printing, the paper is

folded, cut, and arranged into bundles of

pages called signatures. The signatures

are sewn and glued together along the

folded edges. Finally, the book cover is

glued to the signatures. Books can have

either a hard cover or a soft cover.

History

The earliest forms of bookmaking date

back to about 3000 BC. The first ancestors

of books were Egyptian papyrus

rolls. The rolls consisted of a long strip

of paper made from a type of water grass

called papyrus. Other ancient forms

were made of clay tablets, sheets of animal

skin, or bundles of bamboo. The

Chinese invented paper around AD 100.

In Europe people continued to use animal

skins, called vellum or parchment

long after that. The first papermaking

equipment reached Europe in the 1300s.

Early books were difficult to produce.

The text was written by hand.Many

books made in Europe and in the Islamic

world had elaborate drawings. As a

result, books were expensive and hard for

most people to get. Only wealthy,

powerful people and certain scholars and

religious leaders read these early books.

The invention of printing changed that.

In about 1450 a German craftsman

Offset printing is one method of printing.

Text and images appear on a printing plate

(left), which is used to print the book pages.

The stack of printed sheets (right) are ready

to be cut and folded into signatures.

A man works on restoring one of the oldest

copies of the Koran, the holy book of Islam.

Many old books need repairing as they

have started to fall apart over the years.

BRITANNICA STUDENT ENCYCLOPEDIA Book and Bookmaking 109

named Johannes Gutenberg invented a

special type of printing press.

Gutenberg’s press used metal type, or

letter shapes made from metal.

Gutenberg arranged the metal type in

trays to spell out words and sentences.

Then he spread ink onto the metal type

and pressed the trays against sheets of

paper. The trays could be used again

and again.

Gutenberg’s type and press could print

many books quickly. By the 1500s thousands

of printing shops were producing

millions of copies of books. Books

became available to ordinary people for

the first time.

Today books are published in every language.

Personal computers have allowed

people to publish their own books.

Many books can be read or downloaded

from the Internet. This has made books

easier to get than ever before.

#More to explore

Gutenberg, Johannes • Paper • Printing

Boomerang

A boomerang is a curved throwing stick.

People use boomerangs as toys or as

weapons. The Aborigines, the native

people of Australia, have long used boomerangs

for hunting and warfare.

There are two types of boomerangs:

returning boomerangs and nonreturning

boomerangs. Returning boomerangs are

lightweight and have a special curved

shape. A returning boomerang flies in a

circle and comes back to the thrower.

An illustration in an old manuscript shows how books were made long ago. The few

people who knew how to read and write copied the text by hand.

A guide in Australia shows how to throw a

boomerang.

110 Boomerang BRITANNICA STUDENT ENCYCLOPEDIA

People use returning boomerangs for

sporting events and as toys.

Nonreturning boomerangs are not toys.

Ancient peoples used them for killing

prey or enemies. This type of boomerang

is much straighter than a returning

boomerang. It cuts through the air in a

wobbly way.

True boomerangs are found mainly in

Australia.However, people in ancient

Egypt, southern India, and other cultures

also used boomerang-shaped weapons.

Some Native American groups used

boomerang-shaped weapons for hunting.

The first boomerangs were made from a

single piece of carved wood. The carver

heated the wood in hot ashes and then

bent it to get the right shape. Today

boomerangs used for sports are often

made of plywood or fiberglass. Their

shape can be very different from the

curved shape of traditional boomerangs.

#More to explore

Aboriginal Peoples

Boone, Daniel

The American frontiersman Daniel

Boone blazed a trail through the Cumberland

Gap, a pass in the Appalachian

Mountains. His trail opened theWest to

settlement and made him a hero.

Daniel Boone was born in Pennsylvania

on November 2, 1734.He had little

schooling, but he learned to read and

write.He also learned blacksmithing,

weaving, hunting, and trapping. When

he was about 16, he moved with his

family to the North Carolina frontier.He

hunted and trapped in the wilderness.

Boone first passed through the Cumberland

Gap into Kentucky in 1767. In

1773 Boone tried to settle in Kentucky

with his family, but an Indian attack

forced them to turn back. Two years

later a company hoping to make Kentucky

a new colony hired Boone to open

a trail through the gap. The trail Boone

cut was called the Wilderness Road.

Boone built a new settlement, Boonesborough

(now Boonesboro), at the end

of the trail.

Boone became famous as a frontiersman,

but he was still poor. He owned

none of the land he helped open to

settlement. He moved around with his

family, working various jobs. He continued

to hunt and trap. Boone died in

Missouri on September 26, 1820.

#More to explore

Appalachian Mountains • Cumberland

Gap

A detail of a painting from 1851 shows

Daniel Boone escorting settlers through the

Cumberland Gap.

BRITANNICA STUDENT ENCYCLOPEDIA Boone, Daniel 111

Bosnia and Herzegovina

For most of the 20th century Bosnia and

Herzegovina was a part of the country of

Yugoslavia. A civil war in the 1990s

ended with Bosnia and Herzegovina’s

independence. The capital is Sarajevo.

Geography

Bosnia and Herzegovina is located on

the Balkan Peninsula in central Europe.

It is bordered by Croatia, Montenegro,

Serbia, and the Adriatic Sea. Bosnia is

the larger of the two regions. It occupies

the northern and central parts of the

republic.

Bosnia and Herzegovina is a mountainous

country. It has many rivers, including

the Bosna, from which the country

takes its name.

Plants and Animals

Pine, beech, and oak forests cover about

half of Bosnia and Herzegovina. The

country’s varied wildlife includes bears,

wolves, wild pigs, wildcats, chamois

(goatlike animals), otters, foxes, badgers,

and falcons.

People

The major ethnic groups are Bosniacs

(Muslims), Serbs, and Croats. Bosniacs

constitute more than two fifths of the

population, Serbs less than one third,

and Croats less than one fifth. All three

peoples speak the same language, Serbo-

Croatian.

The Serbs are mostly Orthodox Christians,

while the Croats are mainly

Roman Catholic. The Bosniacs are

descended from Slavs who converted to

Islam under the rule of the Ottoman

Empire.

Economy

Almost half of the people work in

manufacturing and mining. Manufacturers

produce cement, steel, and pig

iron. Mines provide coal, iron ore, and

other metals. Trade and services are

other key parts of the economy.

Agriculture and logging are also important.

Crops include corn, potatoes,

wheat, cabbages, oats, plums, and

tobacco.

History

Slavic peoples settled in what is now

Bosnia and Herzegovina in the 500s and

600s. Between brief periods of indepen-

112 Bosnia and Herzegovina BRITANNICA STUDENT ENCYCLOPEDIA

dence, a series of other groups controlled

the region.

The Ottoman Empire conquered Bosnia

in the 1400s. Much of the native population,

mainly landowners, converted to

Islam. In the 1700 and 1800s, tensions

grew between the Muslim landowners

and the Christian peasants, who were

Serbs and Croats.

The Austro-Hungarian Empire officially

claimed the area in 1908. Bosnian Serbs

soon began protesting against Austro-

Hungarian rule. In 1914 a Bosnian

Serb killed Austrian archduke Francis

Ferdinand. The assassination triggered

World War I. After the war Bosnia and

Herzegovina became part of a new

Serbian-controlled kingdom named

Yugoslavia.

AfterWorldWar II Yugoslavia became a

Communist state. When the Communist

government fell in 1989, the tensions

between Serbs, Croats, and

Muslims reemerged. Bosnian Croats and

Muslims wanted an independent republic.

Bosnian Serbs, however, refused to

separate from Yugoslavia.

Shortly after Bosnians voted for independence

in early 1992, a civil war

broke out between Serbs, Croats, and

Muslims. The fighting left more than 2

million people homeless and killed more

than 200,000. The warring parties

finally agreed to peace in 1995. Bosnia

and Herzegovina had gained its independence.

..More to explore

Austria-Hungary • Montenegro

• Ottoman Empire • Sarajevo • Serbia

Fireworks light up the sky at a celebration in Mostar. The city’s bridge was destroyed during

the civil war that broke out in the 1990s. But it was rebuilt and reopened in 2004.

Facts About

BOSNIA AND

HERZEGOVINA

Population

(2008 estimate)

3,858,000

Area

19,772 sq mi

(51,209 sq km)

Capital

Sarajevo

Form of

government

Federal republic

Major cities

Sarajevo, Banja

Luka, Zenica,

Tuzla, Mostar

BRITANNICA STUDENT ENCYCLOPEDIA Bosnia and Herzegovina 113

Boston

Population

(2007

estimate), city,

599,351;

(2008

estimate),

metropolitan

area,

4,522,858

Boston is the capital of the U.S. state of

Massachusetts. The city lies on a harbor

where the Charles River flows into the

Atlantic Ocean. It is one of the oldest

cities in the United States. Boston is a

leading center of education, culture,

medicine, and business in the New

England region.

Insurance, finance, and computer industries

are central to Boston’s economy.

Many important hospitals and universities

are located in the city. In nearby

Cambridge is Harvard University. It is

the oldest university in the United

States. Other important industries in

Boston include food processing, publishing,

and electronics manufacturing.

Boston was one of the first cities that

Europeans settled in what is now the

United States. English settlers founded

the town in 1630. It soon became the

capital of the Massachusetts Bay Colony.

Boston’s fine natural harbor made it an

important city. It grew as a center of

shipping as well as of culture and education.

Two important events happened in Boston

in the years leading up to the American

Revolution. In the Boston Massacre

of 1770 British troops shot at an angry

crowd. In the Boston Tea Party of 1773

colonists dumped shiploads of British

tea into the harbor. They did this to

protest British taxes on tea. During the

war American troops gained control of

the city from the British.

In the 1800s the people of Boston took

a leading role in the movement to end

slavery in the United States. For a time

the city was an important manufactur-

Quincy Market is a shopping and gathering

place in Boston.

The USS Constitution, which is nicknamed

Old Ironsides, was launched from Boston in

1797. It is now part of the Boston National

Historical Park.

114 Boston BRITANNICA STUDENT ENCYCLOPEDIA

ing center. In the late 20th and early

21st centuries the city’s high-technology

and service industries grew.

#More to explore

American Revolution • Massachusetts

Bay Colony

Botany

Botany is the study of plants. It is a

branch of biology. Scientists who work

in the field of botany are called botanists.

Botany is important because people and

animals depend on plants in many ways.

People and animals get food and oxygen

from plants. People also use plants to

make clothing, building materials,

drugs, and countless other things.

Botanists usually focus on a specific area.

Some discover new kinds of plants,

name them, and classify them (group

them with similar plants). Other botanists

study the structure and form of

plants.

Many botanists work as researchers.

Some researchers study plant diseases.

Others experiment with plant chemicals.

Others try to develop plants that are

more useful to humans.

Many botanists are interested in conservation.

Some investigate the effects of

pollution on plants. Others work to

protect rare plants.

Theophrastus, a Greek thinker who

lived in the 300s BC, is considered the

founder of botany. In the 1700s a Swedish

botanist named Carolus Linnaeus

created a system for naming and classifying

plants. Scientists around the world

still use this system today.

#More to explore

Biology • Plant

Botanists make field trips to study

plants in their natural environment.

Children learn how to care for potato plants

at a botanical garden. Such gardens are

designed to teach the public about the

plants that are on display.

BRITANNICA STUDENT ENCYCLOPEDIA Botany 115

Botswana

Since gaining independence in 1966, the

African country of Botswana has

enjoyed a stable government, economic

growth, and harmony between its

peoples. The country’s unspoiled wilderness

draws many visitors. The capital is

Gaborone.

Geography

Botswana is bordered by Zimbabwe,

South Africa, Namibia, and Zambia.

Rivers, including the Chobe, the Limpopo,

and the Molopo, form several of

the borders. The country is almost

entirely flat, with hills only in the southeast

and northwest. The Kalahari Desert

covers most of the south and west. The

Okavango Swamp lies in the northwest.

Much of the country has hot summers

and cooler winters.

Plants and Animals

Savannas, or grasslands with scattered

trees, cover much of Botswana. The

Kalahari has desert grasses and scrub.

True forests occur only in the far north.

Botswana’s wildlife includes lions,

elephants, leopards, giraffes, buffalo,

antelopes, zebras, wildebeests, ostriches,

snakes, and scorpions. Hippopotamuses,

crocodiles, and hundreds of types of

birds live near the rivers.

People

Botswana’s largest ethnic group is the

Tswana, followed by the Kalanga. Scattered

groups of San live in the Kalahari.

About half of the people live in cities

and towns, mainly in the southeast. The

official language is English, but most

people speak Setswana in daily life.

About 40 percent of the people follow

traditional African religions. The rest of

the people are mostly Christians.

Economy

Botswana’s economy is based largely on

mining. The country has rich deposits of

Lions rest in Botswana’s Chobe National

Park.

116 Botswana BRITANNICA STUDENT ENCYCLOPEDIA

diamonds, soda ash (sodium carbonate),

copper, nickel, and coal. Diamonds are

Botswana’s most valuable export. Manufacturers

make cars, beverages, and

bricks. Tourism is a major source of

income.

Livestock raising and farming, the traditional

occupations of the Tswana, still

employ most of the workers. Farmers

raise goats, cattle, and sheep. They grow

sorghum, legumes, and corn.

History

Botswana’s earliest inhabitants were

probably Khoekhoe and San peoples.

Archaeologists believe that these people

first arrived in the region in about

17,000 BC. Bantu-speaking farmers

began migrating to the area in about AD

190. In the 1700s the Tswana people

arrived and established several powerful

states. They soon came to dominate the

country that is now named after them.

In 1867 the discovery of gold excited

European interest in the area. In 1885

the region came under the control of the

British, who called it the Bechuanaland

Protectorate.

In 1966 Bechuanaland gained independence

as the Republic of Botswana. The

country’s first president, Seretse Khama,

promoted democracy and built up the

economy. Problems between Botswana,

Rhodesia (now Zimbabwe), and South

Africa eased in the 1980s and 1990s.

Stability in southern Africa allowed

Botswana to focus on solving its own

problems. In the early 21st century

those problems included a large gap

between the rich and the poor, unemployment,

and a high rate of HIV infection

and AIDS.

..More to explore

Africa • Gaborone • Kalahari

The Okavango River delta in northern Botswana is a vast swampland.

Facts About

BOTSWANA

Population

(2008 estimate)

1,842,000

Area

224,848 sq mi

(582,356 sq km)

Capital

Gaborone

Form of

government

Republic

Major cities

Gaborone, Francistown,

Molepolole,

Selebi-

Pikwe, Maun

BRITANNICA STUDENT ENCYCLOPEDIA Botswana 117

Boxing

Boxing is a sport in which two people

fight with their fists. A boxing competition

is called a match, a fight, or a bout.

A boxer can win by knocking out the

other boxer. A boxer can also win by

scoring more points than his opponent.

A Boxing Ring and Equipment

A boxing match takes place on a square

platform called a ring. The ring is surrounded

by ropes. The ropes keep the

fighters from falling out of the ring.

Each fighter uses a corner of the ring as

a base. During pauses in the fight, the

boxers go to their corners.

A boxer wears padded gloves on each

hand. To protect the teeth, a boxer wears

a mouth guard. Amateur boxers wear

padded headgear.

Weight Classes

Professional boxers are grouped by

weight into more than 12 different

weight classes. The lightest group is the

strawweight or mini-flyweight class.

Fighters in this class weigh no more than

105 pounds (48 kilograms). The heavyweight

class has the heaviest fighters.

Heavyweights usually weigh 190 pounds

(86 kilograms) or more.

A Boxing Match

A boxing match is divided into threeminute

periods called rounds. The boxers

get one minute of rest between

rounds. A professional boxing match is

usually scheduled to last 12 rounds. An

amateur match usually has three scheduled

rounds. A person called the referee

stands inside the ring with the boxers.

The referee makes sure that the boxers

follow the rules.

A boxer can win a match by knockout

(KO) or technical knockout (TKO). A

knockout happens after one boxer hits

the other so hard that the second boxer

falls down. The referee declares a knockout

if the second boxer cannot stand up

within 10 seconds. The referee declares a

technical knockout when a weakened or

injured boxer is no longer able to defend

himself.

Sometimes neither boxer can win a

match by knockout or technical knockout.

Then the winner is decided by

points. Three judges score the match on

scorecards. The judges award points to

the boxers for the number of punches

that they land, or get through their

opponent’s defenses. Boxers also score

points for defensive skill. To win the

match by points, a boxer must have

more points on at least two of the three

scorecards.

Boxing is a sport that requires strength and

stamina.

118 Boxing BRITANNICA STUDENT ENCYCLOPEDIA

History

Fist-fighting contests date back to

ancient times and probably much earlier.

In ancient Greece boxers wrapped their

hands and forearms in leather for protection.

In ancient Rome fighters called

gladiators wore leather hand coverings

that were studded with bits of metal or

metal spikes.

Boxing again became a popular sport in

England in the early 1700s. Boxers then

fought without gloves. An English

fighter named Jack Broughton put

together the first set of boxing rules in

1743. In 1838 a new set of rules banned

kicking, biting, head butting, and hitting

below the waist. The rules were

changed again in 1867. These rules

required boxers to wear gloves.

During the 1900s most of boxing’s

heavyweight champions were from the

United States. Jack Dempsey and Joe

Louis were famous U.S. heavyweight

champions in the first half of the 1900s.

Later champions included Rocky Marciano,

Muhammad Ali, and Joe Frazier.

In the 21st century boxing became

increasingly popular with women. They

now participate in both amateur and

professional matches.

#More to explore

Ali, Muhammad • Gladiator

Boy Scouts

#see Scouting.

Brachiosaurus

Brachiosaurus was one of the tallest of all

dinosaurs. The name Brachiosaurus

means “arm lizard” in Latin. Scientists

call it this because of its long front legs.

Brachiosaurus belongs to the group of

dinosaurs known as sauropods. The sauropods

were plant-eating dinosaurs with

long necks, massive bodies, and four

pillarlike legs.

When and Where

Brachiosaurus Lived

Brachiosaurus lived about 150 to 130

million years ago. Remains of Brachiosaurus

have been found in Europe,

Brachiosaurus

BRITANNICA STUDENT ENCYCLOPEDIA Brachiosaurus 119

Africa, and North America. Brachiosaurus

lived in areas with much plant life,

especially tall trees.

Physical Features

Brachiosaurus could reach more than 75

feet (23 meters) in length and weighed

up to 80 tons. It stood about 40 feet (12

meters) tall from its head to the ground.

The most striking features of Brachiosaurus

were its sloped back and long neck.

Its front legs were longer than its back

legs. It also had a relatively short tail. Its

dome-shaped head was small, and its

snout was somewhat flat. Brachiosaurus

had a few dozen pencil-like teeth.

Behavior

Brachiosaurus lived and traveled in

herds. Scientists believe that Brachiosaurus

could travel at speeds of about 12 to

19 miles per hour (19 to 31 kilometers

per hour). Its size and weight, as well as

sharp claws on its feet, protected it from

meat-eating dinosaurs. Its tremendous

height also allowed Brachiosaurus to

watch for enemies coming from miles

away.

Bradstreet, Anne

One of the first poets in England’s

American colonies was Anne Bradstreet.

Her poems reflect her religion, a strict

form of Christianity called Puritanism.

Anne Bradstreet was born Anne Dudley

in Northampton, England, in about

1612. At age 16 she married Simon

Bradstreet, the son of a Puritan minister.

In 1630 the young couple moved to

America with Anne’s parents and other

Puritans who were setting up the Massachusetts

Bay Colony.

Simon was often away from home, leaving

Anne on her own with their children.

During this time, she began

writing about her family and religion.

She showed her poetry only to her family.

However, her sister’s husband had

her poems published in England in

1650 as a book called The Tenth Muse. It

was the first book of poems written by

an American.

The Bradstreets moved to Andover,

Massachusetts. Anne Bradstreet died

there of tuberculosis in 1672. Her works

were praised by Puritans in her own

time, and they came to be appreciated

once more in the 20th century.

#More to explore

Massachusetts Bay Colony • Puritans

Brachiosaurus

is the largest

and heaviest

land animal

for which scientists

have a

complete set of

fossil bones.

Anne Bradstreet’s poems were

published under the title The

Tenth Muse.

120 Bradstreet, Anne BRITANNICA STUDENT ENCYCLOPEDIA

Braille

Braille is a system that allows blind

people to read and write. It is named

after its French inventor, Louis Braille.

Invention

Louis Braille was born near Paris,

France, on January 4, 1809. He became

blind at the age of 3. At that time blind

people read by touching letters engraved

in wood, cut in cardboard, or cast in

lead. It was a difficult and slow method.

There was no method for writing. As a

schoolboy Braille developed a system of

reading and writing using six dots

punched into cardboard.

Braille published his system in 1829.

By that time he was teaching at the

School for Blind Youth in Paris. The

students there quickly accepted it, but

the teachers did not. It was not until

1854, two years after Braille’s death,

that the school adopted the system.

From there it slowly spread throughout

the world.

The Braille System

Braille is a code of 63 dot patterns called

characters. Each character represents a

letter, combination of letters, common

word, or grammar sign. They are read by

touching them lightly. When preceded

by a number sign (#), the first 10 letters

of the alphabet are read as numbers.

Writing Braille by hand is accomplished

with tools called a slate and stylus. The

slate consists of two metal plates. A sheet

of paper is inserted between the slate’s

two plates. The stylus is a pen-shaped

device used to press the paper against

pits in the lower plate to form raised

dots. A person using Braille writes from

right to left; when the sheet is turned

over, the dots face upward and are read

from left to right. Braille is also produced

by special machines.

Brain

In animals, including humans, the brain

is the control center for the body. As a

part of the nervous system, the brain

receives and makes sense of signals sent

from nerve cells in the body. The brain

also sends information to the body’s

muscles and organs.

The brains of humans and other vertebrates

(animals with a backbone) are

large masses of nerve cells protected by a

skull. Vertebrates’ brains are divided into

several sections. Each section has its own

functions. The brains of invertebrates

(animals without a backbone) are much

simpler.

People read Braille by moving their fingers

over a series of raised dots on a page.

BRITANNICA STUDENT ENCYCLOPEDIA Brain 121

The Human Brain

The human brain is a very powerful

organ. It controls the working of all parts

of the body. It also controls a person’s

thoughts and feelings. The brain helps

the body to stay healthy and to respond

in the right way to its environment.

The brain of an average adult weighs

about 3 pounds (1.4 kilograms). It looks

something like a mushroom. The “cap”

of the mushroom is the cerebrum. It is

the very top of the brain and its largest

part. Its surface has many cracks and

folds. The cerebrum is the “thinking”

part of the brain.

The “stem” of the mushroom is the

brain stem, which is attached to the

spinal cord. The brain stem controls the

things that happen automatically in the

body. These include the heartbeat,

breathing, pleasure, pain, and hunger.

At the back of the head, between the

brain stem and the cerebrum, is the cerebellum.

It controls balance, posture,

and muscles. It also helps in speech.

Brains of Other Animals

The brains of vertebrates other than

humans are divided into three main

sections: hindbrain, midbrain, and forebrain.

In fish and amphibians, the midbrain

is the main center of the brain.

The midbrain is less important in mammals,

birds, and reptiles. These animals

have larger forebrains.

The brains of insects and other

invertebrates are groups of nerve cells.

They are located at the ends of nerve

cords that run through the animal’s

body. This type of brain allows the

animal to control its body and to sense

its environment. Very simple animals

have networks of nerves but no brain.

#More to explore

Nervous System

Most animals have some sort of brain. They

vary greatly in size and shape.

The left side of

the brain controls

the right

side of the

body, and the

right side of

the brain controls

the left

side of the

body.

122 Brain BRITANNICA STUDENT ENCYCLOPEDIA

Brasilia

Population

(2007

estimate), city,

2,348,600;

urban area,

3,507,662

Brasilia is the capital of the South

American country of Brazil. The city lies

on the Parana River. It is famous for the

design of its buildings and for the birdor

airplane-shaped layout of its streets.

Many large companies have offices in

Brasilia. The government of Brazil

employs many people in the city. Many

others work in banking, law, or other

service industries.

Brasilia was built in just a few years,

starting in the late 1950s. Rio de Janeiro

was the capital of Brazil until 1960. In

that year the government offices began

moving to Brasilia. The new city grew

rapidly.

..More to explore

Architecture • Brazil • Rio de Janeiro

Brass

Mixing the metals copper and zinc

together makes brass. Such a mixture of

metals is called an alloy. Brass is often

used to make tools and machine parts.

Sculptors and other artists use brass

because it is easy to shape. Brass

doorknobs, faucets, and towel racks are

found in many homes. Brass is also

used to make such musical instruments

as trombones, trumpets, and French

horns.

Working with Brass

It is possible to work with brass when it

is hot or cold. Hot, melted brass can be

poured into molds of many different

shapes. As the brass cools, it hardens.

Cold brass can be pounded, pressed, or

engraved (scratched with a design).

History

People in western Asia made brass more

than 2,000 years ago. People in ancient

Greece and Rome used brass for

jewelry, armor, and cups and bowls.

From the 1200s to the 1600s people in

Europe made large brass plates to

decorate graves. They also used brass for

church decorations, bowls, candlesticks,

Brasilia is known for its unusual architecture.

These government buildings were

designed by architect Oscar Niemeyer.

Brazil’s leaders

moved the

capital to

Brasilia

because they

wanted people

to move inland

and develop

the country’s

resources.

BRITANNICA STUDENT ENCYCLOPEDIA Brass 123

and locks. People later made clocks,

sundials, and scientific instruments out

of brass. Until steel became widespread

in the middle of the 1800s, cannons

often were made of brass.

..More to explore

Alloy • Metal • Steel

Bratislava

Population

(2006 estimate)

417,653

Bratislava is the capital of the Central

European country of Slovakia. The city

lies on the Danube River. It is Slovakia’s

largest city and center of culture and

education.

Many people in Bratislava work for the

government. Others work in business

offices, banks, and other places that

provide services. Factories in the city

make cloth, chemicals, and electrical

goods. Bratislava is home to a number

of schools, including Comenius

University. The city also has many

museums and theaters.

In ancient times the Celts and Romans

built forts and villages in the Bratislava

region. A group of Slavs known as the

Slovaks arrived in the 500s or 600s. In

the 900s the area became part of the

kingdom of Hungary. Bratislava was the

capital of Hungary for about 250 years

in the 1500s to 1700s. Hungarian lawmakers

met in Bratislava until the mid-

1800s.

In 1918 Slovakia became a part of the

new country of Czechoslovakia.

Bratislava was capital of the province.

In 1993 Slovakia became an independent

country with Bratislava as its

capital.

..More to explore

Slovakia

A store in Egypt displays many trays and

other objects made of brass.

A castle stands on a hill above Bratislava.

The castle burned down in 1811 but was

later rebuilt.

124 Bratislava BRITANNICA STUDENT ENCYCLOPEDIA

Brazil

The largest country in South America,

Brazil takes up about half of the continent.

Brazil’s Amazon River basin,

including the Amazon rain forest, is one

of Earth’s richest areas of plant and animal

life. The capital is Brasilia.

Geography

Brazil shares borders with every South

American nation except Ecuador and

Chile. The Atlantic Ocean lies to the

east. Brazil’s two main geographical

regions are the Amazon River basin in

the north and the Brazilian Highlands

in the center, east, and south. The

northeastern coast is flat and dry. The

southeastern coast includes narrow

plains and mountains. In the westcentral

part of Brazil is a vast wetland

called the Pantanal.

Brazil is the world’s largest tropical

country. It is hot year-round in much of

the country, but temperatures are cooler

along the coast and in the south.

Plants and Animals

The Amazon rain forest has the most

varied plant life on Earth. Animals living

in the trees include tree frogs, salamanders,

monkeys, and swarms of

insects, including many butterflies. Parrots,

macaws, and hummingbirds are

common birds. Larger animals in the

rain forest include jaguars, tapirs,

pumas, and sloths. Along the riverbanks

are found capybaras (the world’s largest

rodents), as well as alligators, boa constrictors,

and turtles. The Amazon River

itself contains electric eels, catfish, piranhas,

manatees, and freshwater dolphins.

Grasslands cover most of the Brazilian

Highlands. In the Pantanal wetland are

great numbers of birds, reptiles, insects,

and such larger animals as anteaters and

armadillos. In the drier northeast the

plant cover is low and spread out.

Thicker woodlands of thorny trees grow

in moister areas.

People

Brazil’s population is a mix of several

different ethnic groups. The country

was a colony of Portugal for more than

300 years. Today, more than half of the

people are white, descendants of the

Portuguese colonists or other European

immigrants. About 40 percent of the

people have a mixture of white and

American Indian or black roots. Smaller

BRITANNICA STUDENT ENCYCLOPEDIA Brazil 125

numbers of people have mainly African,

Asian, or American Indian ancestors.

Most Brazilians speak Portuguese.

Roman Catholicism is the main

religion, though many Indian and

African beliefs are also practiced.

More than 80 percent of Brazil’s people

live in cities or towns, and 13 of those

cities have more than 1 million

inhabitants each. Sao Paulo and Rio de

Janeiro are two of the world’s largest

cities.

Economy

Services—including education, government,

banks, hospitals, restaurants, and

the military—are the largest part of Brazil’s

economy. Manufacturing is the second

most important area of the

economy. The country mainly produces

foods, petroleum products, cars and

trucks, electrical equipment, steel, and

chemicals. Brazil’s industries use its

reserves of iron, silicon, clay, quartz,

gold, coal, petroleum, natural gas, and

wood.

Farmers use less than 10 percent of Brazil’s

land, mostly in the south. However,

Brazil is one of the world’s top producers

of oranges and coffee. Farmers also

grow sugarcane, soybeans, corn, cassava,

rice, bananas, tomatoes, and many other

crops. They raise great numbers of cattle

and hogs.

History

Before the Portuguese arrived in what is

now Brazil, at least 2 million American

1500 mid-1500s 1808 1822 1889 1937 1988

Pedro Alvares

Cabral claims

Brazil for

Portugal.

Brazil begins

importing

millions of

African slaves.

The Portuguese

royal family

moves to

Brazil.

Brazil becomes

an independent

empire.

The emperor is

overthrown;

Brazil becomes

a republic.

President

Getulio Vargas

begins ruling

as a dictator.

Brazil adopts a

new,

democratic

constitution.

T I M E L I N E

The Pantanal is the world’s largest wetland.

126 Brazil BRITANNICA STUDENT ENCYCLOPEDIA

Indians lived there. Many were hunters

and gatherers. Others lived in large villages

and were expert farmers and fishermen.

In 1500 the navigator Pedro Alvares

Cabral claimed the land for Portugal

after landing near what is now Porto

Seguro, Brazil. Portuguese settlers soon

began bringing in Africans to work as

slaves on plantations and, later, in

mines. By 1822, when the slave trade

ended, about 4 million Africans had

been brought to Brazil.

When the French emperor Napoleon I

threatened to invade Portugal in 1808,

the Portuguese royal family fled to Brazil.

They ruled from there and made

Brazil equal with Portugal in the new

United Kingdom of Portugal, Brazil,

and the Algarves. The king returned to

Portugal in 1821, but his son, Dom

Pedro, stayed in Brazil. The next year

Dom Pedro declared Brazil’s independence

from Portugal and became

emperor of the new nation. In 1889 the

emperor Pedro II was forced to give up

his power, and the monarchy came to an

end. Brazil became a federal republic

with an elected government.

Since its independence, Brazil has been

one of Latin America’s most stable

nations, though dictators and the military

have ruled at times. Since 1985

civilian (nonmilitary) presidents have led

Brazil. In 1988 the country adopted a

new constitution that guaranteed basic

social and labor rights. Brazil continued

to struggle to strengthen its economy,

which has suffered from long periods of

rising prices.

..More to explore

Amazon River • Brasilia • Rio de Janeiro

• Sao Paulo

Dancers perform at a parade during the annual festival known as Carnival in Rio de

Janeiro, Brazil.

Facts About

BRAZIL

Population

(2008 estimate)

187,163,000

Area

3,287,612 sq mi

(8,514,877 sq

km)

Capital

Brasilia

Form of

government

Federal republic

Major cities

Sao Paulo, Rio de

Janeiro, Salvador,

Belo Horizonte,

Fortaleza,

Brasilia

BRITANNICA STUDENT ENCYCLOPEDIA Brazil 127

Brazzaville

Population

(2005 estimate)

1,174,000

Brazzaville is the capital of the Republic

of the Congo, a country in west-central

Africa. It is the country’s largest city.

Brazzaville is an important port on the

mighty Congo River. A railroad carries

goods from Brazzaville’s port to a port

on the Atlantic Ocean. TheWorld

Health Organization has an office in the

city. Many people in Brazzaville work

there or in government offices.

An African village known as Ntamo

once stood on the site. In the late 1800s

the French took over Ntamo and

renamed it Brazzaville. They later made

Brazzaville the capital of the French

colonies in west-central Africa.

The Republic of the Congo became an

independent country in 1960. Brazzaville

became its capital. Civil war broke

out in the country several times in the

late 20th and early 21st centuries. The

city was often the site of fighting.

..More to explore

Congo, Republic of the

Brick and Tile

Brick and tile are two different but

closely related building materials. Both

are made from a mixture of clay, sand,

and other fine particles called silt.

Brick

Brick is one of the world’s oldest building

materials. Making bricks is easier

than cutting and hauling stone for

building. The basic steps in brick making

are the same today as they were

thousands of years ago. First, workers

dig up the clay. Sometimes they mix the

clay with sand or other materials to

make it stronger. Next, workers form the

clay into small, rectangular blocks called

bricks. After the bricks dry, workers

bake, or fire, them in very hot ovens

called kilns.

Builders use bricks mainly to make

walls, but floors and walkways can also

be made of bricks. To make strong walls,

builders lay the bricks in interlocking

patterns. This means that each brick lies

on more than one other brick. Builders

People attend a church in Brazzaville. Most

of the people in the Republic of the Congo

practice some form of Christianity.

128 Brazzaville BRITANNICA STUDENT ENCYCLOPEDIA

fill in the spaces between the bricks with

mortar, or sand mixed with cement and

water.

Tile

Like brick, tile is also made from baked

clay. However, tiles are thinner than

bricks. They may also be curved or cut

into geometric shapes. In addition, there

are more kinds of tile than of brick. Tiles

made of red clay, called terra-cotta tiles,

have surfaces that are easy to mold. This

type of tile has long been used for covering

roofs.

When tiles are coated with glaze and

then fired at high temperatures, they are

called ceramic tiles. The glaze gives them

a shiny, colorful appearance and makes

them waterproof. Ceramic tiles cover the

walls and floors of many kitchens and

bathrooms.

Today some tiles are made from plastic

and other artificial materials. Artificial

tiles cover walls and floors in many

modern buildings.

History

The ancient Babylonians made brick

houses 6,000 years ago. The ancient

Egyptians, Greeks, and Romans also

built with bricks and tiles. The Romans

were especially good at making tiles.

They even used tiles to build pipes that

carried water. Native Americans in dry

regions built houses with adobe, or sundried,

bricks.

Early builders often made their bricks

right at the construction site. In the

1800s people developed new and faster

ways of making bricks and tiles. Factories

began producing them in large

quantities. Today many builders use

newer construction materials such as

concrete and cinder blocks. Nevertheless,

brick and tile are still popular building

materials. They are also commonly

used in drainage systems.

#More to explore

Adobe • Clay • Sand

Blue and white tiles decorate

steps in Portugal.

Bricks are laid in an interlocking pattern in

order to build a strong wall.

BRITANNICA STUDENT ENCYCLOPEDIA Brick and Tile 129

Bridge

A bridge is a structure that allows

people and vehicles to cross over an

open space. Bridges span, or stretch

across, deep pits in the earth, bodies of

water, and roads.

Types of Bridges

The beam bridge is the oldest, simplest,

and most common type of bridge. A

beam bridge is a horizontal, or level,

structure. It has a support on each end.

Other supports, called piers, may also

hold up the bridge between the two

ends. A log or a plank that crosses a

stream is a beam bridge in its most basic

form. Modern beam bridges are usually

made of steel beams, called girders. Most

highway bridges are beam bridges.

Like the beam bridge, the truss bridge

has a support at each end. It may also rest

on piers in between. But a truss bridge is

stronger than a simple beam bridge. A

framework of metal or wood bars

connects the two ends of the bridge.

These bars fit together in triangular

shapes. They often form a sort of tunnel

through which the roadway passes.

The cantilever bridge is made up of

structures called cantilevers. A cantilever

is a beam that has a pier at only one end,

like a diving board. A framework of

many bars adds strength to the beam, as

in a truss bridge. At least two of these

beams stretch toward each other to form

a cantilever bridge.

Like the beam bridge, the arch bridge is

a very old design. An arched structure

built beneath the bridge’s roadway provides

its support. Arch bridges often

span rivers and valleys.

In the suspension bridge, the roadway

hangs from strong wires called cables.

The main cables hang between two or

more towers. Smaller cables hang down

from the main cables. The smaller cables

hold up the roadway. Suspension bridges

can span longer distances than any other

type of modern bridge.

A cable-stayed bridge also uses cables to

support the roadway. Its cables run

There are six basic bridge forms. They are

the beam, the truss, the cantilever, the arch,

the suspension, and the cable-stayed.

130 Bridge BRITANNICA STUDENT ENCYCLOPEDIA

directly between the towers and the

roadway. They attach to the roadway in

straight, diagonal lines.

Some types of bridges are movable.

Some may open upward to allow tall

ships to pass underneath. Others may

turn sideways. Still others, called pontoons,

float on water.

History

Early humans built bridges from logs,

branches, or stones. They also made

suspension bridges with long, tough

vines. The ancient Romans built many

stone arch bridges that still exist today.

Modern bridge building began in the

1700s. People began building bridges

from iron and, later, steel. These metals

were stronger and often cheaper than

stone. By 1850 some bridges were

strong enough to support trains.

Concrete became a popular bridge

material in the 1900s. Today engineers

continue to improve bridge-building

techniques.

..More to explore

Concrete • Road • Steel

Bridgetown

Population

(2004

estimate), urban

area, 99,100

Bridgetown is the capital of Barbados,

an island country in the Caribbean Sea.

About half the country’s people live in

the Bridgetown area. The city has the

only seaport in Barbados. Shipping,

banking, and tourism bring money to

Bridgetown. Factories in the city process

sugar and rum.

For a long time Barbados was a British

colony. The British founded the town in

1628. Fires destroyed much of Bridgetown

several times. A disease known as

cholera killed about 20,000 people there

in 1854. In 1966 Barbados became an

independent country with Bridgetown

as its capital.

..More to explore

Barbados

Romans built the Pont du Gard more than 2,000 years ago. The bridge crosses the Gard

River in southern France.

BRITANNICA STUDENT ENCYCLOPEDIA Bridgetown 131

British Columbia

Canada’s only Pacific coast province

is British Columbia. It is a

scenic land of snowcapped peaks,

rushing rivers, and rugged seacoasts.

British Columbia was one of the last

parts of North America to be explored

by Europeans. The capital is Victoria.

Geography

Only the southern half of British

Columbia has a coastline on the Pacific

Ocean. The northern half borders the

U.S. state of Alaska to the west. North

of British Columbia are Yukon and the

Northwest Territories. Alberta lies to the

east. The U.S. states of Montana, Idaho,

andWashington are to the south.

Most of British Columbia is mountainous.

The ranges include the Rocky

Mountains and the Coast Mountains.

Between the mountains are plateaus and

valleys. Most of British Columbia’s rivers,

including the Fraser and the Columbia,

flow to the Pacific Ocean. Along the

coast are hundreds of islands. The largest

is Vancouver Island in the southwest.

People

About two thirds of British Columbia’s

people have roots in Great Britain or

Ireland. Many others have ancestors

from Asia, especially China. British

Columbia has a greater variety of American

Indian peoples than any other part

of Canada. They include the Kwakiutl,

the Nootka, the Haida, and the Salish

(Flathead).

Most of British Columbia’s people live

in the south, near the U.S. border.

About 85 percent of the people live in

cities or towns. Vancouver is the largest

city in the province and the third largest

in Canada. Victoria is the second largest

city.

Economy

Natural resources are key to the

economy of British Columbia. Huge

forests, especially along the coast, provide

wood that is made into lumber,

wood pulp, and paper. Fishing in the

rivers and off the coast brings in valuable

catches of salmon, halibut, herring, and

shellfish. Seafood processing is an

important industry. Mines in the prov-

132 British Columbia BRITANNICA STUDENT ENCYCLOPEDIA

ince produce copper, gold, zinc, coal,

natural gas, and oil. British Columbia

does not have much good farmland

because the land is too mountainous.

But farmers grow fruits and vegetables

and produce dairy products.

Most workers in British Columbia have

jobs in service industries such as

tourism, finance, real estate, health care,

and sales. Millions of people visit the

province each year, especially to see its

spectacular scenery. The money those

people spend is important to the

economy.

History

About 80,000 American Indians lived in

what is now British Columbia when

European explorers arrived. The British

sea captain James Cook visited the coast

in 1778. In 1792 another British

explorer, George Vancouver, sailed

around the island that was later named

for him. In 1793 the Scottish explorer

and fur trader Alexander Mackenzie

reached the Pacific coast after traveling

overland from the east. Fur-trading

companies, including the Hudson’s Bay

Company, set up trading posts and forts

in the region.

In the 1800s Americans began to settle

in the region that is nowWashington

and Oregon. For years the British and

U.S. governments disagreed about the

border between their lands. In 1846 the

border was set, and Vancouver Island

became British territory. In 1849 the

British made the island a colony.

Gold was discovered on the Fraser River

in 1858, and thousands of people came

to the mainland in search of riches. The

mainland was made a colony that same

year. In 1866 the island and the mainland

were combined to form the colony

of British Columbia. In 1871 British

Columbia became a province of Canada.

A railroad linking the province with

eastern Canada was completed in 1885.

This helped spark much development in

British Columbia. In the late 1900s it

became one of Canada’s leading provinces.

..More to explore

Alberta • Canada • Cook, James

• Flathead • Fur Trade • Haida

• Hudson’s Bay Company • Kwakiutl

• Nootka • Northwest Territories

• Rocky Mountains • Yukon Territory

The Coast Mountains overlook the Torres Channel in northern British Columbia.

Facts About

BRITISH

COLUMBIA

Flag

Population

(2006 census)

4,113,487

Area

364,764 sq mi

(944,735 sq km)

Capital

Victoria

Motto

Splendor Sine

Occasu (Splendor

Without

Diminishment)

When British

Columbia

Became a

Province

1871

BRITANNICA STUDENT ENCYCLOPEDIA British Columbia 133

Bronze

Mixing the metals copper and tin creates

bronze. Bronze, like other mixtures of

metals, is called an alloy. Bronze is

harder and stronger than copper. It also

does not wear away as easily as either

copper or tin. For these reasons bronze is

often used to make tools and machinery.

Bronze is also used to make electrical

hardware, springs, fasteners, and coins.

Bronze has been the most popular metal

for making statues and other artistic

objects since ancient times.

Working with Bronze

After melted bronze is poured into a

mold and begins to cool, it expands. As

the bronze expands, it fills in every detail

of the mold. When the bronze cools

further and hardens, it shrinks a little

bit. This makes the final object easy to

remove from the mold. Bronze also

changes colors when exposed to air and

water. This effect is called a patina and

can be very beautiful.

History

People first discovered how to make

bronze more than 5,000 years ago. The

discovery of bronze allowed ancient

peoples to make tools and weapons that

were stronger and longer lasting than

any made before. These advances were

so important that the ancient period of

bronze making came to be called the

Bronze Age. People later began making

statues, church bells, doors, bowls, and

many other objects out of bronze.

#More to explore

Alloy • Bronze Age • Metal

Bronze Age

The Bronze Age was a time in early

human history when people first began

to use tools made of bronze. It began in

some places about 5,000 years ago. It

began later in other places. Learning

how to use bronze led to advances in

many areas of human life.

Background

The earliest humans lived during the

Stone Age. Stone Age humans made

tools and weapons of stone. By about

6500 BC people had learned how to

shape copper into tools and other

objects.

Eventually people learned how to mix

tin with copper to make bronze. They

A bronze figure of a girl was made in

Greece about 2,500 years ago.

134 Bronze BRITANNICA STUDENT ENCYCLOPEDIA

probably discovered how to do this by

accident. In some places copper and tin

are mixed together naturally in the

ground. When ancient metalworkers

melted this mixture, they made a form

of bronze.

Bronze looked like copper. But it was

harder and more useful for making

tools, weapons, and artwork.

Events of the Bronze Age

The Bronze Age began in Greece and

China before 3000 BC. Bronze Age cultures

also developed in Mesopotamia (in

modern Iraq), Egypt, and the Indus

River valley (in modern Pakistan). The

Bronze Age had spread to Great Britain

by about 1900 BC. Peoples outside

Europe, North Africa, Asia, and the

Middle East did not have a Bronze Age.

At first only rich people could afford

bronze. For a long time farmers and

craftspeople used cheaper stone tools to

do their work. But eventually more

people did metalworking as a full-time

job. Metalworkers, other craftspeople,

and farmers came together in cities to

trade their goods. This helped civilizations

to grow. Two new inventions—the

wheel and the ox-drawn plow—also

helped Bronze Age civilizations to grow.

In about 1200 BC people learned how to

shape iron into tools. This began the

Iron Age and ended the Bronze Age.

#More to explore

Bronze • Civilization • Iron Age • Stone

Age

Brooks,

Gwendolyn

The U.S. poet Gwendolyn Brooks wrote

about African American life. She wrote

especially about the everyday lives of

blacks in cities. Her poems describe the

racism and poverty that African Americans

have faced.

People used bronze to make daggers and

other tools during the Bronze Age.

Gwendolyn Brooks

BRITANNICA STUDENT ENCYCLOPEDIA Brooks, Gwendolyn 135

Gwendolyn Elizabeth Brooks was born

in Topeka, Kansas, on June 7, 1917. She

grew up in Chicago, Illinois. She wrote

her first poem at age 7.

Brooks’s first collection of poems was

published in 1945. It was called A Street

in Bronzeville. In 1950 Brooks won an

award called the Pulitzer prize for her

book Annie Allen. The poems are about

a black girl growing up in Chicago.

Brooks was the first African American to

win a Pulitzer prize.

Brooks’s most highly praised collection,

The Bean Eaters, was published in 1960.

It contains some of her most famous

poems, including We Real Cool.Written

in a simple style, We Real Cool describes

the difficulties of poverty on youth.

In addition to poetry, Brooks wrote a

novel based on her life. She also taught

poetry and English at different schools

throughout her career. Brooks died in

Chicago on December 3, 2000.

Brown, John

As an abolitionist, John Brown wanted

to end slavery in the United States.

Unlike most abolitionists, however, he

took the law into his own hands. Opponents

of slavery admired him, but others

considered him a dangerous criminal.

John Brown was born on May 9, 1800,

in Torrington, Connecticut. He moved

to Ohio as a child. As an adult he moved

restlessly from state to state. He tanned

leather and also tried other trades. He

was married two times and had many

children.

For a time he and his family lived in a

black community in New York state. He

had always opposed slavery, but in the

1850s he became more determined to

take action against the practice.

In 1855 Brown found his way to the

Kansas Territory, where groups of settlers

were fighting battles over the issue of

slavery. On May 24, 1856, he and his

supporters killed five men at a proslavery

settlement in Pottawatomie Creek.

Brown’s last raid came on October 16,

1859. He and an armed band attacked a

federal arsenal, or weapons storehouse,

in Harpers Ferry, Virginia (nowWest

Virginia). He hoped that thousands of

slaves would rise in rebellion and follow

him to a new mountain stronghold.

This did not happen, and after two days

he was captured by U.S. troops. Brown

was tried and hanged at Charlestown,

Virginia, on December 2, 1859.

#More to explore

Abolitionist Movement

John Brown

In 1985–86

Gwendolyn

Brooks was

the Library of

Congress consultant

in

poetry. This is

the top honor

for a U.S.

poet.

136 Brown, John BRITANNICA STUDENT ENCYCLOPEDIA

Brunei

The country of Brunei is a small Islamic

sultanate, or kingdom. It lies on the

northwestern coast of the island of

Borneo, also shared by Malaysia and

Indonesia. Large oil and gas reserves

make Brunei one of the wealthiest

nations in Southeast Asia. The capital

and largest city is Bandar Seri Begawan.

The South China Sea and Sarawak, a

state of Malaysia, surround Brunei.

Sarawak divides Brunei into two separate

parts. Coral sand beaches line the

coast. The rest of the country is hilly.

The climate is hot and wet. Seasonal

winds called monsoons bring heavy rain.

Rain forests cover the land.Wildlife

includes lions, tigers, monkeys, birds,

insects, snakes, and lizards.

About two thirds of the population is

Malay. About one tenth is Chinese.

Other native peoples and Asians make

up most of the rest. The main language

is Malay, but many speak Chinese or

English. About two thirds of the population

is Muslim.

The country’s economy depends on its

large reserves of oil and natural gas. Very

little manufacturing exists, aside from

petroleum products. Most people work

in services or construction.

In the early 1400s Brunei became an

independent kingdom. By the 1500s

Brunei controlled almost all of Borneo.

In the 1800s Great Britain took control

of Brunei. In 1959 Brunei gained partial

self-government.

During the 1970s the sultan, or king,

used the gas and oil profits to improve

people’s lives. Health care and education

are still free to all citizens. Brunei became

fully independent in 1984.

..More to explore

A young boy attends school in Brunei. Bandar Seri Begawan • Islam

Facts About

BRUNEI

Population

(2008 estimate)

400,000

Area

2,226 sq mi

(5,765 sq km)

Capital

Bandar Seri

Begawan

Form of

government

Monarchy

Major cities

Bandar Seri

Begawan, Kuala

Belait, Seria

BRITANNICA STUDENT ENCYCLOPEDIA Brunei 137

Brussels

Population

(2007

estimate), city,

145,917;

Brussels-Capital

Region,

1,809,242

Brussels is the capital of Belgium, a

country in northwestern Europe. Brussels

and its surrounding towns make up

the largest metropolitan area in Belgium.

The area is one of the country’s three

regions, called the Brussels-Capital

Region.

Many people come to Brussels to visit

the city’s museums, parks, and public

squares. Others come to work in the

government offices. The government is

the largest employer in the city. Factories

in Brussels process foods and make

cloth, machines, electrical products, and

chemicals. The city has long been

famous for its lace, carpets, furniture,

and art products.

Brussels is also important as a center of

European government and trade. The

city is the headquarters of two major

international organizations—the European

Union and the North Atlantic

Treaty Organization (NATO).

Brussels was settled in the 500s. It developed

around a castle on an island in the

Senne River. The city had many different

rulers over the years. In the 1100s it

began to grow as a center of the cloth

trade. In the 1400s Brussels became a

leading city in an area known for its art

and culture. The Spanish and Austrian

empires later ruled the area for about

200 years.

Belgium became part of The Netherlands

in 1815. Brussels then shared the

status of capital with The Hague. In

1830 Brussels was the main site of a

revolt against The Netherlands. Belgium

then became an independent country

with Brussels as its capital.

..More to explore

Belgium • European Union • North

Atlantic Treaty Organization

Buchanan, James

The 15th president of the United States,

James Buchanan failed to solve the slavery

crisis of the 1850s and 1860s. He

tried to make a compromise between the

North and the South but could not prevent

the American CivilWar.

At the heart of Brussels is the Grand Place.

It is a public square that began as a marketplace

hundreds of years ago.

138 Brussels BRITANNICA STUDENT ENCYCLOPEDIA

Early Life

James Buchanan was born on April 23,

1791, near Mercersburg, Pennsylvania.

His father was a successful storekeeper

and landowner. In 1809 Buchanan

graduated from Dickinson College in

Carlisle, Pennsylvania. He then studied

law and became a lawyer in 1812.

Buchanan never married.

Political Career

Buchanan was elected to the Pennsylvania

House of Representatives in 1814.

He entered the U.S. House of Representatives

in 1821 and the U.S. Senate in

1834. He resigned in 1845 to become

secretary of state under President James

K. Polk. During that time Texas became

a state. This led to a war with Mexico

because Mexico claimed part of Texas.

Buchanan helped settle another border

dispute that came up during his time as

secretary of state. The dispute was with

Great Britain over the boundary

between Canada and the Oregon

Territory.

Buchanan ran for president twice in the

1840s but lost. He became minister to

Great Britain after Franklin Pierce won

the election of 1852. While in Europe

Buchanan helped write the Ostend

Manifesto. That report recommended

April 23, June 1,

1791 1834 1845 1856 1860 1861 1868

Buchanan is

born near

Mercersburg,

Pennsylvania.

Buchanan

becomes a

U.S. senator.

Buchanan

becomes

secretary of

state under

President James

K. Polk.

Buchanan is

elected

president.

Abraham

Lincoln is

elected to

replace

Buchanan as

president.

Seven Southern

states leave the

Union before

Buchanan

leaves office.

Buchanan

dies in

Pennsylvania.

T I M E L I N E

James Buchanan was the 15th president of

the United States.

BRITANNICA STUDENT ENCYCLOPEDIA Buchanan, James 139

that the United States take Cuba from

Spain, by force if necessary. The Ostend

Manifesto increased Buchanan’s popularity

because the nation wanted to gain

more territory.

Presidency

In 1856 the Democratic Party nominated

Buchanan for president and John

C. Breckinridge for vice president.

“Buck and Breck,” as they were called,

won the election.

As president, Buchanan handled foreign

affairs well. At home, however, he

stumbled over the question of slavery.

The split between the slave states of the

South and the free states of the North

widened. Several Southern states threatened

to withdraw from the Union.

Buchanan disapproved of slavery, but he

wanted to hold the country together. He

believed the United States might avoid a

civil war if Northerners stopped protesting

slavery and the government protected

slave owners.

In 1860 the Democratic Party split into

Northern and Southern groups. Neither

group wanted Buchanan as its presidential

nominee. The split led to the election

of the antislavery Republican

candidate, Abraham Lincoln. As Buchanan’s

term was ending, he could not

stop seven Southern states from leaving

the Union. The result was the American

CivilWar, which began in 1861.

Retirement and Death

Buchanan retired to his home near Lancaster,

Pennsylvania, in March 1861.

During his retirement, critics in both

the North and the South attacked him

for his efforts at compromise. Buchanan

died on June 1, 1868, near Lancaster.

..More to explore

American CivilWar • Lincoln, Abraham

• Pierce, Franklin • Slavery • United

States

Bucharest

Population

(2007 estimate)

1,931,838

Bucharest is the capital of Romania, a

country in eastern Europe. It is the largest

city in Romania. Bucharest is also a

center of culture and industry. Several

factories in the city make electrical

equipment and various kinds of

machines. Others make chemicals,

cloth, clothing, and processed foods.

Culture, shopping, and industry help make

Bucharest a lively city.

James

Buchanan was

the only president

who was

never married.

140 Bucharest BRITANNICA STUDENT ENCYCLOPEDIA

People have lived in the Bucharest area

for many thousands of years. By the

mid-1400s it was part of a state called

Walachia. Vlad III, the prince ofWalachia,

built the fort of Bucharest. The

fort was intended to protectWalachia

from attacks by the Turks. Eventually,

however, the Turkish Ottoman Empire

took over the area. Under the Turks

Bucharest became the main economic

center ofWalachia. In 1659 Bucharest

becameWalachia’s capital.

In 1859Walachia became part of the

new country of Romania. Bucharest was

declared the capital of Romania in 1862.

In the early 1900s Bucharest grew as the

most important city of a large country.

DuringWorldWar II (1939–45) Bucharest

was damaged by bombing. After the

war the center of the city was rebuilt.

Building projects made the city larger

and more modern.

..More to explore

Romania

Budapest

Population

(2008 estimate)

1,702,297

Budapest is the capital of Hungary, a

country of central Europe. It is the largest

city in the country. Budapest is also

an important center of culture, education,

and science.

Budapest lies on both banks of the

Danube River. The city has two main

sections: Buda and Pest. These sections

sit on opposite banks of the river. Several

bridges connect them. Buda features

many hills. Pest is fairly flat.

More than 100 natural hot springs are

found in Budapest. Many spas, or

resorts, are built around these springs.

Partly because of this, Budapest is a

major tourist site.

Budapest is also Hungary’s center of

transportation, manufacturing, and

banking. Factories in the city make electronics,

communications equipment,

chemicals, cloth, and processed foods.

Others make buses, railroad equipment,

and boats.

In ancient times the Romans built a

town on the site of Budapest. Hungarians

came to the area in the 800s. They

A statue of Saint Stephen, the first king of

Hungary, overlooks the city of Budapest.

BRITANNICA STUDENT ENCYCLOPEDIA Budapest 141

later settled the town of Buda. Buda

became the capital of the kingdom of

Hungary in the 1400s. Slavic groups

established Pest. German merchants

later developed Pest into a trading town.

Both towns came under Turkish rule for

a period.

Many buildings in Budapest today date

from the 1700s and 1800s. The area was

then under Austrian rule. In 1873 Buda

and Pest joined together to form a single

city.

Fighting at the end ofWorldWar II in

1945 severely damaged Budapest. After

the war Hungary established a Communist

government centered in Budapest.

In 1956 there was an uprising in the city

against the Communist government.

That rebellion failed. In the 1980s more

protests led to the fall of Communism

in Hungary. Budapest was the center of

those protests.

#More to explore

Hungary

Buddha

The founder of Buddhism was the

Buddha, a man born with the name

Siddhartha Gautama. The Buddha was

a man of great wisdom and compassion.

He taught people how to

overcome suffering.

Early Life

Siddhartha Gautama was a prince who

lived sometime in the 500s to 300s BC.

He was born near the border of what

are today Nepal and India. Little is

known for certain about his life, though

there are many stories about him. He is

said to have grown up in luxury,

shielded from aging, sickness, and

death.

The stories about him say that at age 29

Gautama saw a bent old man for the

first time. This greatly troubled

Gautama. His chariot-driver, Channa,

explained that the man was old and that

all people grow old. On another day,

Gautama saw a sick man, and later he

saw a dead body. Channa explained that

all people are subject to sickness and

death. Finally, Gautama saw a monk,

who looked peaceful. Gautama decided

to give up his wealth and become a

monk. He wanted to discover how the

Between the

later 1800s

and 1918,

Budapest was

one of the two

capital cities of

the powerful

empire of

Austria-

Hungary.

Vienna, Austria,

was the

other.

Statues of the Buddha can be found in

many Asian countries.

142 Buddha BRITANNICA STUDENT ENCYCLOPEDIA

monk was able to look peaceful when he

was surrounded by suffering.

Finding and Sharing the Truth

Gautama left home in search of the

truth. One day, while Gautama was sitting

and meditating under a tree, he

became enlightened, or free from both

desire and suffering. In this way, he

became the Buddha, which means

“enlightened one.”

The Buddha taught others about Four

Noble Truths he discovered. The first

truth is that life is full of suffering. The

second is that suffering is caused by

desire. The third is that humans can

free themselves from all that. The

fourth truth told the way to achieve

this freedom.

The Buddha soon attracted followers,

who formed the first Buddhist order, or

sangha. The Buddha sent them out into

the world to spread his message. The

Buddha himself set out traveling, converting

many people on the way. He is

said to have died at age 80, in a city

called Kusinara (now Kasia, India).

#More to explore

Buddhism

Buddhism

The religion based on the teachings of

the Buddha is known as Buddhism.

The Buddha was born with the name

Siddhartha Gautama and lived

sometime in the 500s to 300s BC. He

became enlightened, meaning that he

found a way to free himself from the

cycle of desire and suffering. The

Buddha taught his followers how to

achieve this too.

Buddhism began in India and spread to

central and southeastern Asia, China,

Korea, and Japan. It plays a central role

in the spiritual, cultural, and social life

of Asia. Today some people in theWestern

world also follow Buddhism. At the

beginning of the 21st century Buddhism

was the fourth-largest religion in the

world, with about 360 million followers.

Some Important Buddhist Holidays

Holiday Date

Mahayana Countries

Buddha’s birthday April 8

Buddha’s enlightenment December 8

Buddha’s death February 15

Note: Different countries celebrate these holidays

on different dates.

Theravada Countries

Wesak (Buddha’s one day, usually in

birthday, enlightenment, May, when there is

and death) a full moon

A Buddhist monk beats a drum while other

monks pray.

BRITANNICA STUDENT ENCYCLOPEDIA Buddhism 143

Beliefs and Practices

Buddhism is based on the Buddha’s

teachings, which are called the Four

Noble Truths. The first truth is that life

is made up of pain and suffering. The

second is that all suffering is caused by

one’s desires. The third is that one can

be free of these desires. The freedom

from desire is called nirvana. The fourth

truth is the Eightfold Path, which

explains eight ways to achieve nirvana.

The Eightfold Path is also called the

Middle Path. It teaches that people

should not indulge in too much luxury

and pleasure. But they should also not

harshly deny themselves all worldly

comforts. Instead, people should take a

middle, or balanced, course.

Buddhism has three main parts. These

parts are called the Triratna, or “the

three jewels.” They are: the Buddha, or

the teacher; the dharma, or the teaching;

and the sangha, or the community of

believers. Buddhist monks believe that

the three jewels protect them. This is

expressed in the Buddhist prayer, “I take

refuge in the Buddha. I take refuge in

the dharma. I take refuge in the sangha.”

Divisions

Many years after the Buddha’s death

two major groups appeared among his

followers. One group followed a branch

known as Theravada, meaning “Way of

the Elders.” It is the older and more

conservative branch of Buddhism. Many

people in Sri Lanka, Myanmar, Thailand,

Laos, and Cambodia belong to this

group.

The other group is called Mahayana.

This form of Buddhism is popular in

Mongolia, China (including Tibet),

Japan, Korea, Vietnam, and Nepal. Zen

Buddhism comes from Mahayana

Buddhism.

The Theravada Buddhists concentrate

on freeing themselves through improving

their own lives. Mahayana Buddhists

believe they can achieve enlightenment

through a life of good work for others.

Buddhist monks wear simple robes and

often live in communities called monasteries.

Prayer flags line a walkway near the site

where the Buddha experienced his enlightenment.

144 Buddhism BRITANNICA STUDENT ENCYCLOPEDIA

History

The Buddha began teaching his philosophy

after receiving enlightenment. One

day he sat down under a tree in Bodh

Gaya (now in the state of Bihar in India)

and began meditating. On the 49th day,

he achieved enlightenment and so was

freed from suffering. He became known

as the Buddha, which means “enlightened

one.”

According to tradition, the Buddha lived

and taught for 45 years after his enlightenment.

The Buddha preached in Pali,

which was the language of the common

people. He believed that his teachings

were for everyone and not just scholars.

However, he did not write down his

teachings. The Buddha’s followers

shared his teachings with other people

by word of mouth. These teachings were

not put in writing until many years after

the Buddha’s death.

The Buddha established a religious order

known as the sangha. Many of its members

were wandering monks, as the Buddha

himself had been. After the

Buddha’s death, these monks helped

spread Buddhism through northern

India. In the 200s BC Buddhism gained

a powerful sponsor. Asoka, the ruler of

an empire that spanned most of South

Asia, embraced and promoted the religion.

He built many Buddhist monuments

and monasteries.

Buddhism later declined somewhat in

India. But from India, Buddhism spread

to Sri Lanka and Southeast Asia as well

as through central Asia and Tibet and

into China, Korea, and Japan.

..More to explore

Buddha • Monk

Buenos Aires

Population

(2001 census),

city, 2,776,138;

urban area,

11,460,575

Buenos Aires is the capital of Argentina,

a country of southern South America. It

is one of the largest cities in South

America. The city is a center of business,

politics, and culture. Buenos Aires is also

a leading port. It lies on the Parana

River near the Atlantic Ocean.

The Plaza de la Republica is one of the

major public squares in Buenos Aires.

BRITANNICA STUDENT ENCYCLOPEDIA Buenos Aires 145

Cityscape

Buenos Aires has many plazas and parks.

Its most important public square is the

Plaza de Mayo. The home of Argentina’s

president and other government buildings

surround the square.

There are also many museums and other

cultural sites in Buenos Aires. The

Colon Theatre is a well-known opera

house. It is also home to the national

ballet and symphony. Buenos Aires is

also known as a center for popular dance

and music. The dance called the tango

was born there in the late 1800s.

Economy

The port at Buenos Aires is the largest in

South America. Shipping goods through

the port is important to the city’s

economy. Manufacturing and service

industries also bring money to Buenos

Aires. Factories in the city process foods,

work metals, put together cars, and process

oil. Others make cloth, paper, and

chemicals. Printing, publishing, and

banking are also important.

History

The Spanish founded Buenos Aires in

1580. The city grew gradually over the

next 200 years. In 1776 Buenos Aires

became the capital of a large Spanish

province. Buenos Aires grew rapidly as a

center of trade. In the early 1800s

Argentina became free of Spanish rule.

Buenos Aires became its capital in 1880.

During the 1900s the city’s industries

grew. Buenos Aires suffered economic

problems in 2001. Afterward the

economy began to grow again. But poverty

and crime had become larger problems

in the city.

#More to explore

Argentina

Buffalo

Buffalo are mammals of Africa and Asia.

The American bison is often called a

buffalo, but it is not a true buffalo. Buffalo

are closely related to bison, cattle,

and yaks.

There are several types of buffalo. The

Cape buffalo lives in Africa, often in

grasslands or plains. It is also called the

African buffalo.

The buffalo of Asia include the water

buffalo, the anoa, and the tamarau. The

water buffalo can be found wild in

Southeast Asia. It lives in swamps, forests,

and grasslands near water. People

raise water buffalo as farm animals in

Asia and other parts of the world. They

use these animals to pull farm equip-

The people of

Buenos Aires

call themselves

portenos

because Buenos

Aires is a

port city.

The Cape buffalo is the only kind of buffalo

that lives in the wild in Africa.

146 Buffalo BRITANNICA STUDENT ENCYCLOPEDIA

ment and to carry heavy things on their

backs. People also keep water buffalo for

their milk and meat. Anoas and tamaraus

live in forests in Southeast Asia.

Wild buffalo have become rare in Asia.

Buffalo are heavily built animals. They

range in height from about 2.5 to 6.5

feet (0.75 to 2 meters). Some kinds have

large, curving horns. Other kinds have

straight horns. All buffalo have hooves

on their feet. Most buffalo are mainly

black, brown, or gray.

Except for anoas, buffalo in the wild live

in groups called herds. They spend a lot

of time eating and digesting grasses. To

digest their food, they swallow it and

later bring it back up to the mouth to

chew. This makes the food easier to

digest when they swallow it a second

time.

#More to explore

Bison • Cattle • Mammal • Yak

Buffalo Bill

#see Cody, William Frederick.

Bujumbura

Population

(2004 estimate)

340,300

Bujumbura is the capital of the central

African country of Burundi. The city

lies on Lake Tanganyika. It is the country’s

main port and only large city. The

city was once called Usumbura. The

Germans took it over in the 1890s. Belgium

later controlled the area. In 1962

Burundi became an independent country.

The city was then renamed Bujumbura

and made the capital. It was the

center of a violent conflict in the late

20th and early 21st centuries.

#More to explore

Burundi

People in Asia use water buffalo for many

different purposes. The animals pull plows

and carry heavy loads. They even provide

transportation.

Traditional dancers perform in Bujumbura.

BRITANNICA STUDENT ENCYCLOPEDIA Bujumbura 147

Bulgaria

The Republic of Bulgaria lies on the

Balkan Peninsula in the southeastern

corner of Europe. The neighboring

Turks of the Ottoman Empire controlled

Bulgaria for almost 500 years.

The capital is Sofia.

Geography

Bulgaria’s only coastline is on the Black

Sea, to the east. The Danube River

forms most of Bulgaria’s northern border

with Romania. Bulgaria also shares

borders with Serbia, Macedonia, Greece,

and Turkey.

The Balkan Mountains stretch across the

country. The Maritsa River runs through

the central Thracian Plain, a farming

area. Much of Bulgaria has a continental

climate with warm summers and cold

winters. Highlands tend to be wetter

than the low-lying farming areas.

Plants and Animals

Evergreen trees cover the mountain

slopes. The lowland areas have largely

been cleared for farming. Deer, bears,

wolves, badgers, wild boars, and wildcats

may be found in the more remote

regions.

People

Ethnic Bulgarians make up almost 85

percent of the population. The only

significant minority groups are Turks

and Roma (Gypsies). Bulgarians are

Slavic people who write their language

in the Cyrillic (Russian) alphabet. Bulgaria’s

traditional religion is a branch of

Eastern Orthodox Christianity. More

than two thirds of Bulgaria’s people live

in cities.

Economy

Businesses that serve the public, government

work, manufacturing, and mining

are the most important parts of Bulgaria’s

economy. Bulgaria has deposits of

coal, iron, copper, petroleum, and natu-

People stroll along a boulevard and dine at

sidewalk cafes in Varna, Bulgaria.

148 Bulgaria BRITANNICA STUDENT ENCYCLOPEDIA

ral gas. Manufacturers make petroleum

products, machinery, and clothing.

About one fifth of Bulgarians work in

agriculture, logging, and fishing. Leading

crops are wheat, corn, barley, sunflowers,

and grapes. Bulgarians also grow

roses. The flower’s oil is used in perfume.

Sheep, pigs, goats, and cattle are

the main livestock.

History

What is now Bulgaria was part of an

ancient region known as Thrace. In the

1st century AD the Roman Empire took

over Thrace. Slavs invaded in the 5th

and 6th centuries. The Bulgars, a Turkic

people from north of the Black Sea,

defeated the Slavs and gave their name

to the country.

In the following centuries the Bulgars

and the Slavs became one people and

converted to Christianity. Two Bulgarian

empires followed. The Byzantine Empire

defeated the first empire in about 1018.

The second arose in 1185 but fell to the

Islamic Ottoman Empire in 1396. Bulgarians

lost their independence for

about 500 years, but most of them did

not convert to Islam.

An uprising against the Ottomans failed

in 1876. Two years later, with Russian

help, Bulgaria gained partial independence.

Bulgaria’s leader Prince Ferdinand

declared the country fully

independent in 1908. Bulgaria then

became involved in two wars with its

neighbors on the Balkan Peninsula, as

well as the two world wars.

AfterWorldWar II the Bulgarian

monarchy fell. Bulgaria became a

Communist state under the influence of

the Soviet Union. After the fall of

Communism Bulgaria held elections in

1990 and worked to build a democratic

government.

..More to explore

Balkan Peninsula • Ottoman Empire

• Rom • Sofia

Rock formations in the Balkan Mountains are surrounded by walls and other fortifications.

Centuries ago many different groups used the area to protect against enemies.

Facts About

BULGARIA

Population

(2008 estimate)

7,569,000

Area

42,858 sq mi

(111,002 sq km)

Capital

Sofia

Form of

government

Republic

Major cities

Sofia, Plovdiv,

Varna, Burgas,

Ruse

BRITANNICA STUDENT ENCYCLOPEDIA Bulgaria 149

Bunche, Ralph

U.S. diplomat Ralph Bunche won the

Nobel peace prize in 1950. A diplomat

is a person who helps countries to make

agreements. Bunche won the Nobel

prize in honor of his efforts to make

peace in the Middle East.

Ralph Johnson Bunch (his family added

the final “e” later) was born on August 7,

1904, in Detroit, Michigan. In about

1916, after his parents died, he moved

in with his grandmother in Los Angeles,

California. Bunche was a good student

and a good athlete. He earned a degree

from Harvard University in 1934. He

then taught at Howard University in

Washington, D.C.

DuringWorldWar II Bunche helped to

plan the United Nations (UN), a peaceful

organization of many countries. He

joined the UN staff in 1947. In 1949

Bunche helped Israel and several Arab

nations to make a peace agreement. For

this work he won the 1950 Nobel prize

for peace. Bunche later led other peace

missions. He also worked on the UN

program for peaceful uses of atomic

energy.

Bunche was involved in the civil rights

movement as well. He wanted to help

fellow African Americans gain rights to

such things as better jobs and education.

He was one of the leaders of the

National Association for the Advancement

of Colored People (NAACP) for

more than 20 years. In 1963 he received

the Presidential Medal of Freedom.

Bunche died on December 9, 1971, in

New York City.

#More to explore

Arab-IsraeliWars • Civil Rights

Movement • Nobel Prize • United

Nations

Bunyan, Paul

Many years ago in U.S. lumber camps,

loggers dreamed up wild stories about a

mythical lumberjack, Paul Bunyan.

According to these “tall tales,” neither

giant mosquitoes nor rains that lasted

for months bothered Bunyan or his

companion, Babe the Blue Ox. Other

stories told how Bunyan created the

Grand Canyon. The Great Lakes were

said to have formed when his huge footprints

filled up with water.

The tales of Paul Bunyan first appeared

in print in 1910 in a newspaper. Two

books published in the 1920s helped to

turn Bunyan into a national folk hero.

#More to explore

Storytelling

Bunche was

the first African

American,

and the first

black person

from any

country, to win

a Nobel prize

in any category.

Giant statues of Paul Bunyan and Babe the

Blue Ox greet visitors to a park in California.

150 Bunche, Ralph BRITANNICA STUDENT ENCYCLOPEDIA

Burkina Faso

Located inWest Africa, Burkina Faso

was once named Upper Volta after the

branches of the Volta River that flow

through it. Ouagadougou is the capital.

Burkina Faso is surrounded by Mali,

Cote d’Ivoire, Ghana, Togo, Benin, and

Niger. Much of the land is flat. The climate

is generally hot and dry, but there

is a rainy season. The north is part of the

Sahel, a semidesert region. The south is

semitropical, with wetlands and forests.

Grassland or desert covers much of the

country.Wildlife includes antelope,

lions, elephants, buffalo, hippopotamuses,

monkeys, and crocodiles.

Nearly half of the people belong to the

Mossi ethnic group. Others include

Fulani, Lobi, Bobo, and Mande. French

is the official language, but most people

speak More. About half of the people are

Muslims. The rest follow traditional

religions or Christianity. More than 80

percent of the people live in small towns

or villages.

Most of the people are farmers. Sorghum,

millet, corn, and cotton are the

main crops. Farmers also raise goats,

sheep, cattle, and chickens. Manufacturers

make sugar, cooking oil, flour, beverages,

and bicycles. The country also has

deposits of gold and manganese.

In the 1400s Mossi and Gurma peoples

set up kingdoms in the area. In the late

1800s France took control of the region.

It created the colony of Upper Volta in

1919. Upper Volta gained independence

in 1960. Since then, the military has

overthrown the elected government several

times. In 1984 the government

renamed the country Burkina Faso,

which means “Land of Incorruptible

People.”

..More to explore

Africa • Ouagadougou

Burkina Faso has many small villages.

Facts About

BURKINA FASO

Population

(2008 estimate)

14,391,000

Area

103,456 sq mi

(267,950 sq km)

Capital

Ouagadougou

Form of

government

Republic

Major cities

Ouagadougou,

Bobo-Dioulasso,

Koudougou,

Ouahigouya,

Banfora

BRITANNICA STUDENT ENCYCLOPEDIA Burkina Faso 151

Burma

#see Myanmar.

Burn and Scald

A burn is damage to the skin caused by

fire, hot surfaces, chemicals, electricity,

or radiation. Radiation is energy that

comes from the sun, tanning lamps,

X-rays, some cancer treatments, and

other sources. Burns caused by hot liquid

or steam are called scalds.

How Burns Affect the Body

Doctors classify burns based on how

many layers of skin are damaged. Firstdegree

burns affect only the outer layer,

called the epidermis. They make the

skin red and sore. Sunburns are firstdegree

burns. Second-degree burns

damage the epidermis and some of the

underlying layer, called the dermis.

They are red and painful, and they may

blister.

Third- and fourth-degree burns are very

serious. Third-degree burns damage all

of the epidermis and the dermis. Sometimes

they reach the fatty tissue beneath.

The skin turns leathery and feels numb.

Fourth-degree burns go even deeper.

They destroy the fatty tissue and may

damage the muscles or bone below.

They turn the skin black.

Serious burns cause a condition called

shock. The victim grows pale and is confused

and anxious. Later the blood pressure

drops sharply, and the person may

collapse. Shock happens because a burn

damages the blood vessels in the skin.

This causes the blood to lose important

fluid. This change in the blood affects all

body systems.

Treatment

People can usually treat first-degree

burns themselves. The first thing to do is

to run cool water over the burn. This

stops the burning process. Then they

should clean the burn with soap and

water. Small burns can be left uncovered

to heal. Larger burns can be covered

with a bandage.

Large second-degree burns and all more

serious burns should be treated quickly

by a doctor. Doctors give the person

fluids to stop shock and drugs to prevent

infection.

#More to explore

Fire • Skin

152 Burma BRITANNICA STUDENT ENCYCLOPEDIA

Burundi

Burundi is a country in central Africa. It

has lost hundreds of thousands of people

to violence between its Hutu and Tutsi

ethnic groups. The capital of Burundi is

Bujumbura.

Burundi is bordered by Rwanda, Tanzania,

and the Democratic Republic of the

Congo. Burundi lies close to the equator.

Areas near the equator usually have

a hot climate. But Burundi’s high mountains

keep temperatures mild. There are

dry and rainy seasons each year.

Trees cover the mountain slopes. Grasslands

cover the lower areas.Wildlife

includes lions, leopards, crocodiles, buffalo,

warthogs, and baboons.

More than 80 percent of the people are

Hutu. Only about 15 percent are Tutsi,

but they have traditionally controlled

the government and the military. The

official languages are Rundi and French.

Christianity is the main religion.

The people of Burundi live mainly by

farming. Coffee and tea are important

exports. Farmers also grow bananas,

sweet potatoes, cassava, beans, sugarcane,

and corn. A few manufacturers make

beverages, cooking oil, and sugar.

The first people in what is now Burundi

were probably the Twa Pygmies. The

Hutu likely arrived by the 11th century.

The Tutsi followed 300 or 400 years

later. Tutsi kings then took control of

the region.

In the early 1900s Germany and then

Belgium gained control of the area. In

1962 part of the territory became the

independent monarchy of Burundi.

Fighting soon broke out between the

Tutsi and Hutu. Burundi’s civil war

continued into the 21st century.

..More to explore

Africa • Bujumbura

Drummers in Burundi often perform at

important events.

Facts About

BURUNDI

Population

(2008 estimate)

8,691,000

Area

10,740 sq mi

(27,816 sq km)

Capital

Bujumbura

Form of

government

Transitional

government

Major cities

Bujumbura,

Gitega, Muyinga,

Ngozi, Ruyigi

BRITANNICA STUDENT ENCYCLOPEDIA Burundi 153

Bush, George

After serving two terms as vice president,

George Bush became the 41st

president of the United States in 1989.

The main event of Bush’s presidency

was the Persian GulfWar.

Early Life

George HerbertWalker Bush was born

on June 12, 1924, in Milton, Massachusetts.

His family later moved to Greenwich,

Connecticut. George was the

second of five children born to Prescott

Sheldon Bush and DorothyWalker

Bush. His father was a banker and later a

U.S. senator.

In 1942 Bush joined the U.S. Naval

Reserve. As a Navy pilot, he flew many

missions in the Pacific duringWorld

War II. In 1945 Bush married Barbara

Pierce. After the war he attended Yale

University and earned a degree in economics.

Bush then moved to Texas,

where he helped start three companies

dealing in oil and drilling equipment.

Political Career

As a member of the Republican Party,

Bush ran for the U.S. Senate in 1964

June 12,

1924 1966 1976 1980 1988 1991 1992

Bush is born

in Milton,

Massachusetts.

Bush is elected

to the U.S.

House of

Representatives.

Bush becomes

the head of

the Central

Intelligence

Agency.

Bush is elected

vice president

under President

Ronald

Reagan.

Bush is elected

president.

The United

States and

allies defeat

Iraq in the

Persian Gulf

War.

Bush loses the

presidential

election to Bill

Clinton.

T I M E L I N E

George Bush was the 41st president of the

United States.

154 Bush, George BRITANNICA STUDENT ENCYCLOPEDIA

but lost. Two years later he was elected

to the House of Representatives. In

1970 he gave up his House seat to run

again for the Senate. Again he lost.

President Richard Nixon then made

Bush the U.S. ambassador to the United

Nations. From 1974 to 1976 he represented

the United States in China. Bush

then spent a year as director of the Central

Intelligence Agency.

In 1979 Bush ran for president. He

withdrew from the race in 1980 to

become Ronald Reagan’s vice presidential

running mate. The Reagan-Bush

team easily defeated President Jimmy

Carter and Vice PresidentWalter F.

Mondale. Reagan and Bush were

reelected in 1984.

Presidency

In 1988 Bush again decided to run for

president. He chose Senator Dan

Quayle as his running mate. Bush

defeated the Democratic candidate,

Michael Dukakis, and was sworn in as

president in January 1989.

President Bush was especially interested

in foreign policy. In December 1989 he

ordered a military invasion of Panama to

topple that country’s dictator, Manuel

Noriega.

In August 1990 the Middle Eastern

country of Iraq invaded Kuwait. Bush

formed an international alliance and

sent U.S. military forces to Saudi Arabia

to convince Iraq to leave Kuwait. When

Iraq refused, Bush ordered an air attack.

The Persian GulfWar, which lasted

from mid-January to late February

1991, ended with the freeing of Kuwait.

The U.S. victory made Bush very popular.

Bush’s popularity soon fell, however, as

the U.S. economy suffered. In addition,

Bush broke his promise not to increase

taxes. In 1992 Bush lost the presidential

election to Bill Clinton. Bush retired to

Houston, Texas.

Political Heirs

Bush and his wife had four sons and two

daughters. His first son, GeorgeW.

Bush, served as governor of Texas before

being elected president in 2000.

Another son, Jeb Bush, became governor

of Florida in 1998.

#More to explore

Bush, GeorgeW. • Carter, Jimmy

• Clinton, Bill • Persian GulfWar

• Reagan, Ronald • United States

Bush, GeorgeW.

The son of former president George

Bush, GeorgeW. Bush became the 43rd

president of the United States in 2001.

A Republican, Bush won the office in

one of the closest presidential elections

in U.S. history. In 2004 voters elected

Bush to a second term.

Early Life and Career

GeorgeWalker Bush was born on July 6,

1946, in New Haven, Connecticut. The

eldest son of George and Barbara Bush,

he grew up in Midland and Houston,

Texas. In 1968 he graduated from Yale

George Bush

was the first

person since

1836 to be

elected president

while

serving as vice

president.

BRITANNICA STUDENT ENCYCLOPEDIA Bush, George W. 155

University with a degree in history. He

then served as a pilot in the Texas Air

National Guard. In 1973 he began

studying at Harvard University. He

graduated in 1975 with a master’s

degree in business.

Bush returned to Midland and started

an oil business. In 1977 he married

LauraWelch. The couple had twin

daughters. In 1978 Bush ran for a seat

in the U.S. House of Representatives but

lost. He worked as an adviser and

speechwriter on his father’s campaign

during the 1988 presidential election.

Bush then joined a group that bought

the Texas Rangers baseball team.

Governor

In 1994 Bush ran for governor of Texas

and won. He reformed Texas’ welfare

system and fought crime. He also cut

taxes and increased spending for schools.

Bush was reelected in 1998 with a

record 69 percent of the vote.

Election of 2000

In 2000 Bush ran for president with

Richard Cheney as his vice presidential

running mate. His opponent was Al

Gore, vice president under President Bill

Clinton.

July 6, September 11, March 20,

1946 1994 2000 2001 October 2001 2003 2004

Bush is born in

New Haven,

Connecticut.

Bush is elected

governor of

Texas.

Bush defeats

Al Gore in the

presidential

election.

Terrorists crash

airplanes into

the World

Trade Center

and the

Pentagon.

The United

States attacks

the Taliban

rulers in

Afghanistan.

U.S. and allied

forces invade

Iraq.

Bush defeats

John Kerry to

gain a second

term as

president.

T I M E L I N E

George W. Bush was the 43rd president of

the United States.

156 Bush, George W. BRITANNICA STUDENT ENCYCLOPEDIA

In the election more people voted for

Gore than for Bush. But in a presidential

election a candidate must win the

votes of a group of people known as the

electoral college. That contest was very

close. The outcome depended on

Florida, as both candidates needed its

electoral votes to win. The vote in

Florida was also very close, and for several

weeks Florida recounted its votes.

Eventually the U.S. Supreme Court

stopped the recounts. That decision

made Bush the winner in Florida and

the next president. Bush took office on

January 20, 2001.

Presidency

Bush had the advantage of working with

a Republican-led Congress. Soon after

his election he signed a major tax cut

into law.

Bush faced his greatest challenge on

September 11, 2001. Thousands died

after terrorists flew hijacked airplanes

into theWorld Trade Center in New

York City and the Pentagon inWashington,

D.C. Bush called for a global war

on terrorism. He identified Osama bin

Laden, the leader of a group called

al-Qaeda, as the main suspect in the

attacks. Bush ordered air attacks against

the government of Afghanistan, which

he accused of helping bin Laden. The

government fell by the end of the year.

In 2002 Bush turned his attention to

Iraq. Bush accused Iraq’s president, Saddam

Hussein, of supporting al-Qaeda

and of having banned weapons. In

March 2003 a U.S.-led force invaded

Iraq.Within a few months the force

overthrew Iraq’s government, and in

December Saddam was captured. U.S.-

led troops remained in Iraq to help the

country form a new government. However,

fighting continued.

Many people protested the war, as well

as the poor U.S. economy. Nevertheless,

in 2004 Bush was elected to a second

term. He defeated Democrat John

Kerry.

During his second term Bush appointed

two people to the Supreme Court. But

he continued to face problems related to

the ongoing war and the economy.

These issues made Bush and other

Republicans very unpopular. They

helped Democrat Barack Obama defeat

Republican John McCain in the presidential

election in 2008. Bush left office

in January 2009 and returned to private

life in Texas.

..More to explore

Bush, George • Clinton, Bill • Electoral

College • Iraq • Obama, Barack

• Terrorism • United States

Butterfly and

Moth

Butterflies and moths are related kinds

of flying insects. There are about

100,000 species, or types, of butterflies

and moths. They live in many different

habitats nearly all over the world.

Physical Features

Butterflies and moths vary greatly in

size. The length of their wings spread

George W.

Bush was the

second U.S.

president

whose father

had also been

president. The

first was John

Quincy

Adams, whose

father was

John Adams.

BRITANNICA STUDENT ENCYCLOPEDIA Butterfly and Moth 157

out ranges from about 0.2 inch to 12

inches (4 to 300 millimeters).

Butterflies and moths have many features

in common. Like all insects, they

have six legs. Most adults have two pairs

of wings. Dustlike scales cover the

wings, body, and legs.

There are several differences, however,

between butterflies and moths. Butterfly

antennas, or feelers, are slender and end

in little knobs. Moth antennas lack these

knobs. They often look like tiny feathers

or threads. In addition, butterfly wings

are usually brightly colored or boldly

patterned. Most moths have a duller

color than butterflies do.

Behavior

Most butterflies are active during the

daytime, while moths generally are

active at night. Nearly all butterflies and

moths eat plants. The adults of many

species drink a sweet liquid called nectar

from flowers. As they feed, a substance

called pollen rubs off on them. When

they move to the next flower the pollen

falls onto that flower. The pollen helps

the flowers produce seeds.

Some butterflies and moths travel long

distances to reach their breeding

grounds. In autumn the monarch butterflies

of North America fly nearly

2,000 miles (3,200 kilometers) to the

south. In the spring they breed and then

travel back north. This pattern of travel

is called migration.

Life Cycle

Butterflies and moths change form completely

over the course of their lives.

This change is called metamorphosis.

First, they hatch from an egg as a larva,

or caterpillar. Caterpillars have no

wings, and they often look like fat

worms. Some kinds are hairy.

After a period of growth, the caterpillar

changes into a form called a pupa. The

pupa lies inactive for weeks or months

while its adult features develop. Some

species make a silk case called a cocoon

to protect themselves during this resting

stage. In fact, people get silk from the

cocoons of certain moth caterpillars,

called silkworms. Finally, the butterfly or

moth becomes a winged adult.

..More to explore

Insect • Metamorphosis • Pollen • Silk

All butterflies and moths start out as caterpillars. Some, such as the monarch butterfly, form

a cocoon to protect themselves as they become a pupa. When they are fully grown they

come out of the pupa as an adult butterfly.

158 Butterfly and Moth BRITANNICA STUDENT ENCYCLOPEDIA

Byzantine

Empire

The Roman Empire ruled a large part of

Europe and northern Africa for hundreds

of years. But in AD 395 it split into

two parts. Invaders conquered the western

part in 476. The eastern part became

known as the Byzantine Empire and

lived on until 1453. Its name came from

the ancient city of Byzantium (now

Istanbul, Turkey). This city, under the

name of Constantinople, was the capital

of the Byzantine Empire.

Culture

At its largest size, the Byzantine Empire

extended from the Middle East to

southern Spain. It included parts of

southern Europe and northern Africa

around the Mediterranean Sea. The

people of this large empire developed a

unique culture. They made colorful pictures,

called mosaics, out of broken bits

of stone. They built buildings with large

domes. They also replaced the Latin

language with Greek.

In addition, the Byzantines created a

new branch of Christianity. In 1054 the

Byzantine church separated from the

Christian church in the west. The western

church became known as Roman

Catholicism. The Byzantine church

became known as Eastern Orthodoxy.

Rule of Justinian

Many emperors ruled the Byzantine

Empire. One of the greatest was Justinian

I. He ruled from 527 to 565. During

his reign he expanded the empire and

built many monuments, including a

church called the Hagia Sophia. He also

gave his people a famous code, or collection

of laws.

Challenges and Decline

From the beginning, the Byzantine

Empire faced many invasions. In the

early years, groups from Europe threatened

the empire’s borders. The early

Byzantines also fought Persians from

Asia and Muslims from Arabia.

During the 1300s, Muslim Turks conquered

the lands surrounding Constantinople.

In 1453 the Turks captured the

city. They made it the capital of the

Ottoman Empire.With that the Byzantine

Empire came to an end.

..More to explore

Eastern Orthodox Churches • Ottoman

Empire • Rome, Ancient

The Byzantine Empire is known for its art.

A mosaic showing the Empress Theodora

is in the San Vitale Basilica in Ravenna,

Italy.

The Turks

made the

Church of

Hagia Sophia

into a mosque

(Islamic house

of worship).

Now the

building is a

museum.

BRITANNICA STUDENT ENCYCLOPEDIA Byzantine Empire 159

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Encyclopedia

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eBook edition January, 2010

The cabbages include such

familiar vegetables as cauliflower,

broccoli, and brussels

sprouts.

(See Cabbage.)

Cockroaches have lived on

Earth for more than 320 million

years.

(See Cockroach.)

Red, blue, and green are the

primary colors of light. The primary

colors of pigments are

magenta, yellow, and cyan.

(See Color.)

A meteor shower happens

when Earth passes through the

orbit of some comets.

(See Comet.)

Cork is made from the bark of

a kind of oak tree.

(See Cork.)

Cc

Cabbage

The group of plants called cabbages

includes a number of familiar vegetables.

Among them are head cabbage, broccoli,

cauliflower, brussels sprouts, kale, and

collard. All kinds of cabbage developed

from the same plant, called wild cabbage.

They are grown in mild climates

throughout the world.

Cabbage plants have leaves with a waxy

coating. This coating usually gives the

leaf a gray-green or blue-green color.

The flowers have two petals and two

petal-like parts called sepals. The petals

and sepals are arranged in opposite pairs

in the form of a cross. The flowers grow

in loose clusters at the top of the stem.

Cabbages can be grouped according to

the parts that are used for food. In some

forms the leaves are eaten. These include

kale, kohlrabi, head cabbage, and brussels

sprouts. Kale and kohlrabi have

loose leaves that spread outward from a

stem. In the case of kohlrabi the stem is

also eaten. Head cabbage has tightly

folded leaves that form a single large

head around a stem. Brussels sprouts are

like head cabbages but are much smaller.

Many brussels sprouts grow along a

stem. Other cabbages, such as cauliflower

and broccoli, have thickened

flowers that are eaten.

#More to explore

Flower • Plant

Cabot, John

After the news of Christopher Columbus’

famous trip to the Americas reached

England, King Henry VII sent John

4 Cabbage BRITANNICA STUDENT ENCYCLOPEDIA

Cabot to seek new lands for the English.

Cabot reached North America in 1497.

His landing led England to claim what

is now Canada.

Like Columbus, John Cabot was born in

Genoa, in what is now Italy, in about

1450. His original name was Giovanni

Caboto. By 1461 Cabot had moved to

Venice, Italy. During the 1470s Cabot

sailed to the eastern part of the Mediterranean

Sea as a trader. He visited Mecca,

a great trading center in Arabia.

By 1495 Cabot was living in Bristol,

England. He believed that he could find

a short route to Asia. His plan was to sail

north and west across the Atlantic

Ocean. In 1496 King Henry VII agreed

to the trip. Bad weather, food shortages,

and conflicts with his crew forced Cabot

to turn back.

The next year Cabot sailed again with a

crew of 18 men on the small ship Matthew.

On June 24, 1497, the men

reached North America. They explored

the coast of what is now Canada, in

either Newfoundland and Labrador or

Nova Scotia. The ship may also have

reached what is now the U.S. state of

Maine. In August 1497 Cabot returned

to Bristol.

The next year the king sent Cabot on

another trip. Cabot thought that he

could reach Japan by sailing south along

the coast he had found. Cabot left

England with five ships. One ship

stopped in Ireland. The other four ships

never returned. Cabot may have reached

North America again, or he may have

died at sea.

#More to explore

Columbus, Christopher

Cactus

Cactuses, or cacti, are desert plants.

They grow in dry places where other

plants have trouble living. Their ability

to store water keeps them alive. Cacti are

A picture shows John Cabot claiming what

is now Canada in the name of King Henry

VII in 1497.

There are several different varieties of barrel

cactus. In general they have strong, stiff

spines and prominent ribs.

BRITANNICA STUDENT ENCYCLOPEDIA Cactus 5

also protected by sharp spines, or

needles. These discourage animals from

eating them.

Where Cacti Grow

There are about 1,650 species, or types,

of cactus. These plants grow mainly in

the dry areas of the United States,

Mexico, Central America, and South

America. Mexico has the greatest number

and variety of cacti.

Physical Features and Growth

Cacti are succulent plants. This means

that they have thick tissues that take up

and hold large amounts of water. The

stored water keeps them alive during

dry periods. Unlike many plants, cacti

do not have deep roots. Instead they

have roots that spread out near the

surface of the soil. This is important to

their survival. These roots absorb water

from a wide area during the few times

it rains.

Cacti are known for their pointy spines.

These grow in different patterns on the

plant’s surface. Some cacti also have

flowers and branches. Most do not have

leaves. If a cactus has leaves, they are

very small and fall off as the plant grows.

Cacti come in many sizes. The cactus

called the prickly pear grows in low

bunches. The giant cactus known as the

saguaro can be 50 feet (15 meters) tall.

Its branches may be 2 feet (about 0.6

meter) thick.

Most cacti grow in the ground. Some

cacti, known as epiphytes, grow on

plants. Others may grow on hard things

such as rocks.

Uses

Cacti are often grown for decoration.

Many unusual and beautiful varieties are

prized as houseplants. In South America

cacti are sometimes used as fences. The

U.S. state of Arizona has adopted the

saguaro as its state flower.

Some types of cacti are also grown for

food. The egg-shaped fruit of the

saguaro can be eaten. People also eat the

fruit of the prickly pear.

Caddo

The Caddo were a group of about 25

Native American tribes that originally

lived in the area that is now the U.S.

states of Louisiana, Texas, Arkansas, and

A type of cactus known as the Engelmann

prickly pear commonly grows in the southwestern

United States.

6 Caddo BRITANNICA STUDENT ENCYCLOPEDIA

Oklahoma. They built their villages on

fertile lands along the Red River.

The Caddo got most of their food by

farming. They grew corn, pumpkins,

squash, and beans. They also used bows

and arrows to hunt deer, bear, and small

game animals. They lived in domeshaped

houses made from grass stuffed

into a wooden frame.

In the 1540s the Caddo welcomed

Spanish explorers into their territory.

Spanish and French traders visited regularly

by the early 1700s. The Caddo

traded their corn to other tribes for animal

furs. They then gave the furs to the

French in exchange for European goods.

As more and more non-Indians arrived,

the Caddo began to lose their lands. By

the mid-1800s they fled to Indian Territory

(now Oklahoma). There they

settled on a reservation along the

Washita River, which they shared with

theWichita Indians.

By the end of the 20th century, there

were about 3,000 Caddo in the United

States. Many lived in tribal lands in

Oklahoma.

#More to explore

Native Americans

Caesar, Julius

The general and dictator Julius Caesar

helped to build ancient Rome into a

mighty empire. The name Caesar

became the Russian word tsar and the

German kaiser. Both mean “emperor.”

Julius Caesar was born on July 12 or 13,

in about 100 BC. His father died when

Caesar was 16. Caesar’s family was patri-

The Caddo people made this small human

figure in the early 1800s.

Julius Caesar was a leader of ancient

Rome. He built a mighty empire. This

marble bust of Caesar is in the Capitoline

Museum in Rome.

BRITANNICA STUDENT ENCYCLOPEDIA Caesar, Julius 7

cian, or upper class, but they supported

the common people in politics.

Rise to Power

Caesar studied public speaking and later

entered politics. In 59 BC he was elected

consul, the highest public office in

ancient Rome. As one of two consuls, he

ruled the Roman state for one year.

He then left Rome to govern a Roman

province in Gaul (modern France). In

nine years of fighting he brought all of

Gaul under Roman rule.

Dictator of Rome

Caesar returned to Italy in January of 49

BC and made himself dictator. Five years

of civil war between Caesar’s forces and

the supporters of the popular general

Pompey followed. Pompey fled to Egypt

and died there before Caesar could catch

him. But Caesar continued to fight and

win battles against Pompey’s supporters.

When he returned to Rome, Caesar

pardoned his old enemies and gained

many supporters. Not everyone trusted

Caesar, however. Many wanted Rome to

be a republic governed by a group of

people rather than a dictatorship led by

one man alone.

Sixty senators agreed to a plan to kill

Caesar onMarch 15 (the “Ides of

March” in the Roman calendar), 44 BC.

Among them was Caesar’s friendMarcus

Junius Brutus. As he died, Caesar said,

“Et tu, Brute?” (“You too, Brutus?”).

..More to explore

Augustus • Dictator • Rome, Ancient

Cairo

Population

(2006

estimate), city,

6,759,000;

(2005

estimate), urban

area,

11,128,000

Cairo is the capital of Egypt, a country

in northeastern Africa. It is the largest

city in Africa. Cairo has long been the

cultural center of the Arab world.

Places of Interest

Two areas, new and old, make up Cairo.

Modern Cairo faces the Nile River. It

includes the central business district and

newer living areas.

In Cairo’s oldest areas many people live

in crowded conditions. Many ancient

monuments are found there. The City

of the Dead is a large section of historic

cemeteries along the edge of the city.

Thousands of poor people live among

the tombs there. The Great Pyramids at

Giza lie along the outskirts of Cairo.

Economy

Cairo has long been an important trading

center. Factories in the city make

cotton, processed foods, paper, cigarettes,

and many other products. Most

of Egypt’s important banks, shipping

companies, airlines, and hotels are in

Cairo. The city’s museums and monuments

attract many tourists.

The ancient

Romans

named the

month of July

in honor of

Julius Caesar.

8 Cairo BRITANNICA STUDENT ENCYCLOPEDIA

History

People have lived in the area around

Cairo for thousands of years. In AD 969

Egypt’s rulers at the time established a

new city. It was later named Cairo.

In the 1200s Cairo became the capital of

a large Muslim empire. The city thrived

as a center of trade and Islamic learning

and culture. Most of Cairo’s greatest

buildings went up during that period.

After other rulers took over in the 1500s

the city went into a period of decline.

In the 1860s many European-style

buildings were built in new city districts.

In 1922 Egypt became an independent

country with Cairo as its capital. Since

then the city has grown and grown.

#More to explore

Egypt • Egypt, Ancient • Nile River

• Pyramid

Calendar

A calendar is a tool used to mark the

passing of time. People of ancient times

based their calendars on the most obvious

regular events they knew—the

changing positions of the sun, moon,

and stars. These calendars helped them

figure out when to plant and harvest

their crops. Over time different groups

of people developed other calendars

based on their own needs and beliefs.

Days, Weeks,

Months, and Years

Several units of time are common to

almost all calendars. The day is the most

basic unit. The day measures the cycle of

daytime and nighttime. It is now known

to be the length of time that Earth takes

to spin once on its axis. A group of

seven days is called a week.

The month is about 29 1/2 days long, the

time taken by the Moon to orbit Earth.

The year is about 365 1/4 days long. That

is the time taken by Earth to orbit the

sun. The year measures the seasons.

Fitting months into years is a problem

for calendar makers. The difficulty

comes from the fact that the month is

lunar, or based on the Moon, but the

year is solar, or based on the sun. Twelve

cycles of the Moon take about 354 days,

not 365 1/4. To make the lunar months

fit into the solar year, it is necessary to

add days at certain times. This is why

calendar months differ in length. All

except February are longer than 29 days

to make up for the extra 11 days of the

solar year. For the same reason a day is

added to February every fourth year.

These are called “leap years.”

Modern Cairo’s blocks of apartments, office

buildings, and shops line the Nile River.

Unlike the day,

the month,

and the year,

the week is not

based on any

astronomical

event.

BRITANNICA STUDENT ENCYCLOPEDIA Calendar 9

Early Calendars

The Sumerians of ancient Mesopotamia

(now Iraq) used a calendar of 12 lunar

months. They added an extra month

about every four years. This calendar

served as a model for early Greek and

Jewish calendars.

The early Egyptians also used a calendar

based on the Moon. Later, though, the

Egyptians worked out a calendar that

corresponded almost exactly to the seasons.

The early Romans had a lunar year of

355 days. To make the lunar year agree

with the solar year, priests added extra

months. The calendar became increasingly

out of phase with the seasons.

Julian and Gregorian

Calendars

In 46 BC, the Roman ruler Julius Caesar

decided on the figure of 365 1/4 days for

the length of the year. Every fourth year

had 366 days. This calendar was named

“Julian” after its creator. It had the 12

months at the lengths used today.

The Julian year was still slightly longer

than the solar year, however, and problems

arose as the centuries passed. In

1582 Pope Gregory XIII ordered 10

days to be dropped from the year. To

keep the calendar correct in the future,

Gregory ordered that leap year should be

skipped three times in every 400 years.

His system is called the Gregorian calendar.

It is now used almost everywhere

outside the Islamic world.

Native American Calendars

The Maya and the Aztec had the best

Native American calendars. Their calendars

each had a cycle of 260 named days

related to their religious rituals and a

year of 365 days. The year was divided

into 18 months of 20 days each, with

five days added to fill out the years.

Other Calendars

Several calendars other than the

Gregorian calendar are still in use. The

Muslim calendar, for example, is used

by most Arab countries. It is a lunar

calendar with 12 months of 30 or 29

days that add up to a year of 354 or

355 days.

The Chinese calendar is still used along

with the Gregorian calendar in China,

Taiwan, and neighboring countries. The

traditional Hindu and Jewish calendars

continue to be used as well for religious

purposes.

#More to explore

Aztec • Caesar, Julius • Maya • Season

Great Britain

and its colonies

lost 11

days when

they switched

from the Julian

to the Gregorian

calendar

in 1752. The

day after September

2 was

September 14.

A Jewish calendar from the 1800s is written

in Hebrew.

10 Calendar BRITANNICA STUDENT ENCYCLOPEDIA

California

More people live in California than in

any other U.S. state. About one eighth of

the country’s entire population lives in

the state. California even has more

residents than about half of the world’s

countries. The state’s name is believed to

have come from a Spanish novel of the

1500s that described a fabled place called

California. The nickname of the Golden

State comes from the golden poppies

that grow in California and from the

gold that was found there in the mid-

1800s. Sacramento is the capital.

Geography

California is one of the country’s largest

states in area; only Alaska and Texas are

bigger. It borders Nevada and Arizona

on the east, Oregon on the north,

Mexico on the south, and the

Pacific Ocean on the west.

California’s landscape is varied, with

mountains, valleys, forests, seacoasts,

and deserts. The Klamath Mountains

are in the state’s northwest corner. To

their east is the southern part of the

Cascade Range. The Sierra Nevada is a

wall of mountains in the east-central

part of the state. The Central Valley

runs north to south between the Sierra

Nevada on the east and the highlands

of the Pacific Coast Ranges. Most of

eastern California is desert. The largest

desert in the state, the Mojave, is in the

southeast.

California’s climate differs by location.

The climate along the Pacific coast is

generally mild. The Central Valley has

hot summers and mild to cool winters.

The mountains have short summers and

cold winters. The southeastern desert is

very hot and dry.

People

The majority of California’s people are

of European descent, but the state’s

minority groups are large. More than

one fourth of California’s residents were

born outside the United States. Mexicans

are the largest foreign-born group

by far. People from the Philippines,

China (including Hong Kong and Taiwan),

Vietnam, and El Salvador are

other large groups. Mexicans and other

Hispanics make up about one third of

California’s population. African Ameri-

BRITANNICA STUDENT ENCYCLOPEDIA California 11

cans make up more than 6 percent.

California’s Native American population,

numbering more than 330,000, is

the largest in the country.

The largest clusters of people are in the

south, around Los Angeles and San

Diego, and in the San Francisco Bay

Area. Los Angeles is the largest city in

the state and the second largest city in

the country. Bay Area cities include San

Francisco, Oakland, and San Jose.

Economy

California’s economic production ranks

first among the 50 states. If California

were a country, it would have one of

the world’s largest economies. Services

account for about three fourths of the

state’s economy. Service-related jobs

include workers such as actors, social

workers, government employees,

schoolteachers, doctors and nurses,

lawyers, and restaurant and hotel staff.

Tourism is an important service

industry. Each year it contributes about

75 billion dollars to the state’s

economy.

The Golden Gate Bridge connects San Francisco

to Marin County. It is between San

Francisco Bay and the Pacific Ocean.

The scenic coastline of Big Sur stretches for 100 miles (160 kilometers) along the Pacific

Ocean in California.

12 California BRITANNICA STUDENT ENCYCLOPEDIA

California manufactures automobiles,

aircraft, ships, military supplies, electrical

equipment, and chemicals. California

also has many food-processing plants

and publishing and printing industries.

A region known as Silicon Valley, in the

San Francisco Bay Area, is home to

much of the country’s computer industry.

The motion picture industry is centered

in the Los Angeles area.

California’s farms are the most productive

in the country. The dozens of crops

grown include grapes for eating and

winemaking, citrus fruits, and nuts.

Dairy farms produce milk, cheese, and

other products.

History

Native Americans of the Shasta, Pomo,

Miwok, and Chumash tribes lived along

the Pacific coast of what is now California

long before Europeans arrived. The

Mojave lived in the southeast and the

Yokut in the Central Valley.

Spaniards were the first Europeans in

California. Juan Rodriguez Cabrillo

claimed the land for Spain in 1542. In

1602 Sebastian Vizcaino explored the

coast and gave many places their present

names. In 1769 two Spanish priests

founded a mission called San Diego de

Alcala. During the next 50 years 20

more missions were established along

the coast. Towns and large ranches grew

around the missions.

Between the 1820s and the 1840s

Mexico and the United States competed

for California. Mexico owned the territory

and refused to sell it to the United

States. In 1846 Californians around

Sonoma, near San Francisco, rebelled

against Mexican rule and joined the

United States in fighting the Mexican

War. The peace treaty that ended the

war in 1848 gave California and other

Mexican land to the United States.

Early in 1848, before the treaty was

signed, gold had been discovered near

Coloma, in northern California. This

find started a gold rush. The arrival of

tens of thousands of gold hunters called

forty-niners (because many of them

arrived in 1849) changed California.

The population surge helped lead to

statehood for California in 1850.

Many more people came to California

after railroad service from the eastern

United States began in 1869. During

the Great Depression of the 1930s thousands

of homeless farm families moved

to the state hoping to earn a living. DuringWorldWar

II (1939–45) California’s

industries, such as aircraft plants

and shipyards, greatly expanded. Many

people moved to the state for work and

stayed after the war.

In the early 21st century California continued

to attract new residents, including

many from Mexico. The state had to

deal with issues such as creating affordable

housing and educating people from

many different backgrounds.

..More to explore

Gold Rush • Los Angeles • MexicanWar

• Missions, Spanish • Sacramento

• Sierra Nevada

Facts About

CALIFORNIA

Flag

Population

(2000 census)

33,871,648—

rank, 1st state;

(2008 estimate)

36,756,666—

rank, 1st state

Capital

Sacramento

Area

163,696 sq mi

(423,970 sq

km)—rank, 3rd

state

Statehood

September 9,

1850

Motto

Eureka (I Have

Found It)

State bird

California quail

State flower

Golden poppy

BRITANNICA STUDENT ENCYCLOPEDIA California 13

Caliphate

The Caliphate was the name of the

lands ruled by Muslims from AD 632 to

1258. The leaders of Islam after the

prophet Muhammad had the title of

caliph, which means “successor” in Arabic.

The caliphs built an empire that

stretched from India in the east to Spain

in the west.

The First Caliphs

Islam began in the Arabian Peninsula in

the early 600s. Muhammad, the founder

of Islam, died in 632. Muslims then

chose Abu Bakr to lead the Muslim

community. He became the first caliph.

He and the three caliphs who followed

him—!Umar I, !Uthman, and !Ali—

were relatives of Muhammad.

Some Muslims rebelled against !Ali. This

brought about a split in Islam that still

exists today. The followers of !Ali

became the Shi!ite branch. The followers

of Mu!awiyah I, who was !Ali’s main

opponent, became the Sunnites.

The Umayyad Caliphate

By 661, Mu!awiyah had become the first

of a line of caliphs called the Umayyads.

Under their rule, Muslim armies took

over North Africa and most of the Iberian

Peninsula (now Spain and Portugal)

in Europe.

Eventually, some Muslims rebelled

against the Umayyads’ rule. Forces of

the !Abbasid family defeated the last

Umayyad caliph in battle in 750.

The !Abbasid Caliphate

The !Abbasid family started a new line

of caliphs. The early !Abbasid caliphs

supported trade, the arts, and the sciences.

One caliph, called al-Ma#mun,

tried to make peace with the Shi!ites but

failed.

The !Abbasids turned their attention

away from the area around the Mediterranean

Sea. Instead, they looked eastward

and made Baghdad (in what is

now Iraq) their capital. They also took

on many soldiers from non-Arab

peoples, particularly the Turks.

An Umayyad caliph is pictured on a gold coin from the 600s.

14 Caliphate BRITANNICA STUDENT ENCYCLOPEDIA

End of the Caliphate

The Buyids of Persia (now Iran)

conquered the !Abbasids in 945. The

Seljuq Turks took over in 1055. The

caliph became mainly a religious leader.

Mongol raiders killed the last real

!Abbasid caliph in Baghdad in 1258.

After that, people first in Egypt and

then in the Ottoman Empire (centered

in Turkey) claimed to be caliphs.

However, most Muslims did not

recognize their power.

#More to explore

Abu Bakr • Islam • Muhammad

Calligraphy

Calligraphy is the art of beautiful handwriting.

Artists who create calligraphy

are called calligraphers. They often use a

special pen or a brush to make their art.

Calligraphy in Europe

Writing first developed more than 5,000

years ago. It was not until about the

500s BC, however, that some people

began to use writing as a kind of decoration.

The Greeks were the first to use

one kind of writing for everyday documents

and another for more important

texts. Later Europeans based their calligraphy

on Greek and Roman styles.

Until about the 1400s few people knew

how to write at all. Religious men called

monks used calligraphy as they copied

and decorated religious books. Students

and professional copyists also knew how

to write. Some used calligraphy while

others used more simple forms.

By the 1400s many more people were

learning how to write. In order to make

writing a practical and easy skill, letters

were simplified. At the same time the

printing press was invented. This used

simple letters that could be easily combined

to print a page. Calligraphy lost

importance until the late 1800s. Then it

became a popular hobby.

Calligraphy in Other Cultures

In China people consider calligraphy to

be a high art form, like poetry or painting.

Chinese calligraphers use brushes

with ink on silk or paper. They do not

change the look of the characters (the

symbols of the Chinese language) by

adding decorations.

Hebrew calligraphy is one of the oldest

forms of writing. It has kept its basic

style for hundreds of years. Copies of the

Torah (the Jewish holy writings) are

written by hand in Hebrew calligraphy.

Arabic calligraphy has been an important

art form in the Islamic world since

the 600s. Arabic letters are easily linked

Calligraphy is an important art in Japan.

Many Japanese schoolchildren enter calligraphy

contests.

People often

hire professional

calligraphers

to write

out wedding

invitations or

other special

documents.

BRITANNICA STUDENT ENCYCLOPEDIA Calligraphy 15

for an artistic look. Mosques (Islamic

places of worship) often contain

examples of Arabic calligraphy.

#More to explore

Arts • Monk • Printing •Writing

Calvin, John

The French religious thinker John

Calvin was one of the leaders of the Reformation.

Calvin and others wanted to

change, or reform, the Roman Catholic

church. Instead the Reformation led to

the creation of a new branch of Christianity

called Protestantism. This

became one of the three major branches

of Christianity.

Calvin was born on July 10, 1509, in

Noyon, France. He studied religion and

law during the 1520s. He also became

involved in the movement to reform

Roman Catholicism. The Catholic

church encouraged people to do good

works and to perform rituals in order to

get to heaven. But the reformers

thought that God alone decided who

went to heaven, and not because of

their actions.

In 1533 Calvin moved to Switzerland,

where he studied religious ideas,

especially those of a German priest

named Martin Luther. Like Luther,

Calvin began to reject Roman

Catholicism. Calvin began writing

down his new Protestant beliefs. He

published these beliefs in a book, which

inspired many people to become

Protestants.

Calvin became well known and moved

to Geneva (now in Switzerland). He

worked with other leaders to make this

city-state into an important center of

Protestantism. Calvin also eventually

convinced Geneva’s leaders to follow his

ideas about government. He thought

that governments should make laws

based on religious beliefs.

Calvin died in Geneva on May 27,

1564. After his death his followers,

called Calvinists, spread his ideas across

Europe. In the 1600s some English Calvinists

brought Calvinism to North

America. Today many people view

Calvin as the founding father of several

Protestant churches, including the

Reformed and Presbyterian churches.

#More to explore

Luther, Martin • Protestantism

• Reformation • Roman Catholicism

John Calvin was one of the first leaders of

the branch of Christianity called Protestantism.

He stressed faith in God above all else.

16 Calvin, John BRITANNICA STUDENT ENCYCLOPEDIA

Cambodia

The Southeast Asian country of Cambodia

has long served as a battleground

between various countries and political

groups. The capital is Phnom Penh.

Geography

Cambodia is bordered by Laos, Thailand,

and Vietnam. The Gulf of Thailand

lies to the southwest. A low-lying

plain covers central Cambodia. In the

east the Mekong River runs through

highlands. The Tonle Sap (Great Lake)

and mountains lie in the west. Cambodia

has a tropical climate with a rainy

season and a dry season. In the lowlands

temperatures rarely drop below 80° F

(27° C).

Plants and Animals

Dense forests cover two thirds of Cambodia.

Tall evergreen trees, bamboo,

vines, and palms grow in the northern

mountains. The southwestern highlands

contain pine forests in the higher regions

and rain forests near the sea. Rice paddies,

fields of crops, and grasslands cover

the central plain.

Cambodia’s northern forests contain

elephants, wild oxen, rhinoceroses,

tigers, and leopards. The birds native to

Cambodia include herons, pelicans,

cormorants, and pheasant. The country

also has crocodiles and cobras.

People

The Khmer ethnic group makes up

about 85 percent of the population.

Chinese, Vietnamese, and Cham people

also live in Cambodia. Buddhism is the

main religion. Many rural people also

follow ancient folk religions. More than

80 percent of the population lives in

rural areas.

The Royal Palace in Phnom Penh, Cambodia,

is built in the traditional Cambodian

style.

BRITANNICA STUDENT ENCYCLOPEDIA Cambodia 17

Economy

About 70 percent of Cambodians are

farmers. The main crop is rice. Other

crops include cassava, corn, sugarcane,

bananas, coconuts, oranges, rubber, soybeans,

and tobacco. Cambodians also

fish and raise livestock, including cattle,

pigs, and buffalo.

Trade and manufacturing are important

parts of the economy. Cambodia’s main

products are clothing and textiles,

leather, foods, rubber goods, and logs.

History

People have lived in what is now

Cambodia for at least 6,000 years. The

most famous of Cambodia’s ancient

kingdoms was the powerful Khmer

Empire. The Khmer ruled much of

Southeast Asia from the AD 800s to the

1200s. They constructed the famous

temples of Angkor Wat in the 1100s. In

the 1300s and 1400s the neighboring

Tai peoples invaded, and Cambodia lost

much of its territory. In the 1800s

Thailand and Vietnam further divided

the country.

In the late 1800s France took control of

the region. The French merged Cambodia

with Vietnam and Laos to create the

colony of French Indochina. France

granted Cambodia its independence in

1953.

During the 1960s and 1970s the VietnamWar

spilled over into Cambodia. In

1975 a group of Communists known as

the Khmer Rouge seized control of the

country. Led by a man named Pol Pot,

the Khmer Rouge killed anyone who

opposed the new government. At least 1

million Cambodians died in what came

to be known as the “Killing Fields.”

In 1978 Communist forces backed by

Vietnam invaded Cambodia and

toppled the Khmer Rouge government.

They set up a new government and

changed the name of the country to

Kampuchea. Khmer Rouge rebels continued

to fight the government.

Vietnam pulled out of the country (once

again known as Cambodia) in 1989. In

1993 a new Cambodian government

banned the Khmer Rouge. However, the

rebels did not stop fighting until Pol Pot

died in 1998. Although the civil war was

over, political quarrels and violence continued.

..More to explore

AngkorWat • Mekong River • Phnom

Penh • VietnamWar

A woman in Cambodia works in a rice

paddy. A paddy is a type of wet farmland.

Facts About

CAMBODIA

Population

(2008 estimate)

14,242,000

Area

69,898 sq mi

(181,035 sq km)

Capital

Phnom Penh

Form of

government

Constitutional

monarchy

Major urban

areas

Phnom Penh, Bat

Dambang, Sisophon,

Siem Reab,

Preah Sihanouk

18 Cambodia BRITANNICA STUDENT ENCYCLOPEDIA

Camel

Camels are large mammals that live and

work in several of the world’s deserts.

They are known for their humps. The

Arabian camel, or dromedary, has one

hump on its back. The Bactrian, or

Asian, camel has two humps. Camels

belong to the same family as the llama

and the alpaca.

Where Camels Live

The Bactrian camel lives in the highlands

of central Asia. Most Bactrian

camels are domesticated, or tamed to

help humans. Small herds of wild Bactrians

live in Mongolia and northwestern

China.

The Arabian camel lives mainly in

North Africa, the Middle East, and

India. There are no wild Arabian camels

left in these places. However, herds of

wild Arabian camels now live in Australia.

They are the descendants of tame

camels that people brought to Australia

in the 1800s.

Physical Features

Camels weigh up to about 1,400 pounds

(650 kilograms). They are about 7 feet

(2 meters) tall at the hump. The hump

is made of fat and muscle. Camels have

a long neck, a small head, and a split

upper lip. Long eyelashes protect the

eyes from sandstorms and glaring sun.

The nostrils can close to keep out blowing

sand. Camels stand on four long

legs. Each foot has two hoofed toes. A

scruffy, sand-colored coat of hair covers

the body.

Behavior

Camels are well adapted to living in

deserts. They feed on thorny plants,

shrubs, and dried grasses. They can go

for days or even months without water.

If a camel goes without food and water,

the fat in its hump can nourish it for

several days. The hump then becomes

limp and leans to one side or disappears

altogether.

The Bactrian camel is also called the Asian

camel. It has two humps.

The Arabian camel is also known as a

dromedary. It has only one hump.

BRITANNICA STUDENT ENCYCLOPEDIA Camel 19

Digital Cameras

A digital camera works in a similar way

as a traditional camera. However, it captures

the image on an electronic chip

rather than on film. The chip is a light

sensor that turns the image into electric

signals. Most digital cameras have a

small screen that displays the image

right away. The camera can also store

the image on a memory card. Photographers

can transfer the stored image to a

computer. This allows them to view,

e-mail, or print out the image.

Movie and Video Cameras

Movie cameras are like traditional cameras,

but they record moving images.

They do this by taking many still pictures

in a row—usually 24 or 30 each

second. They record images on a reel of

film. When a movie projector shows the

pictures on the film one after the other,

the images appear to be moving. Video

cameras, or camcorders, record moving

images on magnetic tape. Digital camcorders

store moving images as electric

signals.

History

In ancient times people used a camera

obscura to view eclipses of the sun. They

stood in a small, dark room that had

only a tiny hole to let in light. An

upside-down image of the scene outside

appeared on the wall across from the

hole. Later, people made portable boxes

that worked like the ancient camera

obscura. A mirror reflected the image

outside the box and onto a screen.

In 1837 a Frenchman, Louis Daguerre,

found a way to record the images made

by a camera obscura on metal plates.

These pictures were called daguerreotypes.

Around the same time an Englishman

named William Henry Fox Talbot

used a similar box to record images on

paper. These men had created the first

modern cameras.

In the late 1800s the U.S. inventor

George Eastman made a camera that

brought photography to the general

public. Before this time cameras were

heavy, complicated, and expensive. Eastman’s

camera was small and easy to use.

People simply pushed a button to take

pictures and then sent the film to Eastman’s

factory to be printed.

The U.S. inventor Thomas Edison and

the French Lumiere brothers developed

movie cameras in the late 1800s.

Digital cameras did not appear until the

1990s.

#More to explore

Edison, Thomas • Lens • Light • Movie

• Photography

Digital cameras are easy to use and film

free. They are especially handy for taking

snapshots.

BRITANNICA STUDENT ENCYCLOPEDIA Camera 21

Cameroon

The West African country of Cameroon

takes its name from the Rio dos Camaroes

(River of Shrimps), the name the

Portuguese gave to the Wouri River. The

capital is Yaounde.

Cameroon is bordered by Nigeria,

Chad, the Central African Republic,

Republic of the Congo, Gabon, and

Equatorial Guinea. The Atlantic Ocean

lies to the west. Mountains run through

the north and west. The country has hot

temperatures year-round.

Rain forests are in the south. Mangroves

grow along the coasts and rivers. Monkeys

live in the forests. Elephants,

baboons, and antelope live in the

wooded grasslands of the north.

The ethnic groups of Cameroon include

the Fang, the Bamileke, the Duala, and

the Fulani. English and French are the

official languages, but people speak many

other languages. The majority of the

people follow Christianity or traditional

religions. The north is mostlyMuslim.

Cameroon’s economy is based on farming.

The main crops include cassava,

sugarcane, corn, bananas, and sorghum.

The country also produces petroleum

(oil), lumber, and cocoa for export.

Humans have lived in what is now

Cameroon for at least 50,000 years.

Eventually Bantu people settled in the

south and the west, and the Fulani settled

in the north. In the 1470s the Portuguese

established sugar plantations and a slave

trade. Germany gained control in the late

1800s. AfterWorldWar I Cameroon was

divided into French and British zones. In

1960 the French zone became the

independent republic of Cameroon.

..More to explore

Yaounde

People gather to buy and sell goods at a

market in Maroua, Cameroon.

Facts About

CAMEROON

Population

(2008 estimate)

18,468,000

Area

183,569 sq mi

(475,442 sq km)

Capital

Yaounde

Form of

government

Republic

Major cities

Douala, Yaounde,

Garoua, Maroua,

Bafoussam

22 Cameroon BRITANNICA STUDENT ENCYCLOPEDIA

Canada

Canada is the largest country in the

world after Russia. The country is

divided into 10 provinces and three territories.

The capital is Ottawa.

Geography

Canada lies north of the United States

in North America. The U.S. state of

Alaska sits on its northwestern border.

The Pacific, Atlantic, and Arctic oceans

form the rest of its borders.

Canada’s largest natural region is a

rocky, mostly flat area that covers the

eastern, central, and northwestern parts

of the country. In the west, plains stretch

from the Arctic Ocean to the U.S. border.

The Mackenzie, Canada’s longest

river, drains the northwest.West of the

plains are the Canadian Rocky Mountains.

Along the Pacific are the Coast

Mountains. In the south and southeast,

lowlands border the Great Lakes and

Saint Lawrence River.

Because of its size, Canada has great

variety in its climate. Most regions have

very cold and long winters. Temperatures

are most moderate along the

Pacific coast.

Plants and Animals

One of the largest evergreen forests in

the world stretches from Alaska to Canada’s

Atlantic coast. In the south, the

evergreens are mixed with maple, beech,

red oak, and white ash trees. In the far

north is cold land known as tundra,

where only mosses, lichens, and low

shrubs grow.

Many of Canada’s wild animals live in

the northern forest. Among them are

moose, beavers, Canada lynx, black

bears, wolves, and snowshoe hares. Seals,

polar bears, caribou, white foxes, and

snowy owls live in the tundra. The animals

of the plains include deer and antelope.

Fish are plentiful in Canada’s

waters.

People

Nearly half of the people in Canada

have British ancestors, and almost one

fourth have French ancestors. Smaller

groups of people descended from other

European, Asian, or U.S. immigrants.

There are also small groups of American

Indians and Inuit, as well as Metis

(people with both Indian and European

Banff National Park is in southwestern

Alberta, along the Canadian Rocky Mountains.

Facts About

CANADA

Population

(2008 estimate)

33,213,000

Area

3,855,103 sq mi

(9,984,670 sq

km)

Capital

Ottawa

Form of

government

Federal parliamentary

state

Major metropolitan

areas

Toronto, Montreal,

Vancouver,

Ottawa-Hull, Calgary,

Edmonton

BRITANNICA STUDENT ENCYCLOPEDIA Canada 23

ancestors). Both English and French are

official languages.

About three fourths of Canadians are

Christians. About one sixth of Canadians

follow no religion. The country also

has small groups of Muslims, Jews, Hindus,

and people of other faiths.

Most people live in cities and towns in

the south. The largest city is Toronto,

Ontario, Canada’s business center. The

second largest city is Montreal, Quebec.

It is a major seaport and one of the biggest

French-speaking cities in the world.

Vancouver, British Columbia, is Canada’s

third largest city.

Economy

The economy of Canada is based on

manufacturing and businesses that serve

the public. Among the many service

industries are finance, health care, education,

and tourism. The most valuable

manufactured goods include chemicals,

electronic products, metals, and wood

and paper goods. Canada is also a leading

producer of petroleum (oil), natural

gas, and minerals.

Canada is one of the world’s top food

producers. It is known for its grains,

especially wheat, and oilseeds. Pigs and

cattle are the most important livestock.

Fishers catch salmon, herring, cod, and

other fish in Canada’s waterways.

24 Canada BRITANNICA STUDENT ENCYCLOPEDIA

History

Early Peoples and Exploration

For thousands of years, Inuit lived in the

north and American Indian peoples

lived in the south of what is now

Canada. Vikings from northern Europe

arrived in what is now Newfoundland in

about 1000 AD. The Vikings did not

stay in Canada, however.

In 1497 the Italian explorer John Cabot

landed in eastern Canada. Others soon

followed. In 1534 a French explorer,

Jacques Cartier, entered the Gulf of

Saint Lawrence in what is now Quebec.

He claimed the area for France.

New France

In 1608 Samuel de Champlain founded

the city of Quebec, France’s first permanent

Canadian colony. The French soon

set up more settlements in the region,

which they called New France.

Meanwhile, the British also became

interested in the region. In 1670 the

English started Hudson’s Bay Company,

which built trading posts around Hudson

Bay. Over the next century Great

Britain and France fought wars over the

land. After defeating France in the

French and IndianWar in 1763, Britain

took control of Canada. They made

New France into the colony of Quebec.

British North America

By the late 1700s Britain ruled the lands

that would become the provinces of

about

1000 1497 1605 1763 1867 1982 1999

Vikings arrive

in what is now

Newfoundland.

John Cabot

explores the

eastern coast of

Canada.

Samuel de

Champlain

founds a

French colony

in Nova Scotia.

Great Britain

gains control of

New France.

New Brunswick,

Nova Scotia,

Ontario, and

Quebec form

the Dominion

of Canada.

Canada

gains full

independence

from Great

Britain.

Nunavut

becomes

Canada’s third

territory.

T I M E L I N E

People eat outside at a restaurant in Montreal,

in the Canadian province of Quebec.

BRITANNICA STUDENT ENCYCLOPEDIA Canada 25

Newfoundland, Prince Edward Island,

Nova Scotia, New Brunswick, and Quebec.

Britain divided Quebec into Upper

and Lower Canada in 1791.

In the mid-1800s people began to call

for a union of these colonies. In 1867

Nova Scotia, New Brunswick, and

Upper and Lower Canada (now the

provinces of Ontario and Quebec)

formed the Dominion of Canada. Canada

now had its own federal government,

although Britain kept some

control.

Westward Expansion

The population of Canada increased

quickly during the 1800s. As settlers

moved westward, new provinces and

territories were created. Many native

peoples lost their land and moved to

reserves.

The provinces of Prince Edward Island,

Manitoba, Saskatchewan, Alberta, and

British Columbia, as well as Yukon and

the Northwest Territories, joined the

country by the 1930s. The province of

Newfoundland joined Canada in 1949.

Independence

In 1982 the British Parliament granted

Canada control over its constitution.

This made Canada an independent

country though it kept ties to Britain.

Beginning in the 1960s many French

Canadians in Quebec called for separation

from Canada. They wanted to create

a French-speaking nation. In 1995

the people of Quebec narrowly voted

against separating from Canada. Some

French Canadians continued to call for

separation, however.

In the 1990s many native people asked

the Canadian government to return

their land to them. Canada responded

by creating Nunavut, a self-governing

homeland for the Inuit, in 1999. The

new territory was formed from the eastern

part of the Northwest Territories.

..More to explore

Cabot, John • Cartier, Jacques

• Champlain, Samuel de • Eskimo

• Great Lakes • Hudson Bay • Ottawa

Prime Ministers of Canada

Name Political Party Term

John Macdonald Liberal-Conservative 1867–73

Alexander Mackenzie Liberal 1873–78

John Macdonald Conservative 1878–91

John Abbott Conservative 1891–92

John Thompson Conservative 1892–94

Mackenzie Bowell Conservative 1894–96

Charles Tupper Conservative 1896

Wilfrid Laurier Liberal 1896–1911

Robert Borden Conservative 1911–20

Arthur Meighen Conservative 1920–21

Mackenzie King Liberal 1921–26

Arthur Meighen Conservative 1926

Mackenzie King Liberal 1926–30

Richard Bennett Conservative 1930–35

Mackenzie King Liberal 1935–48

Louis Saint Laurent Liberal 1948–57

John Diefenbaker Progressive Conservative 1957–63

Lester Pearson Liberal 1963–68

Pierre Trudeau Liberal 1968–79

Joseph Clark Progressive Conservative 1979–80

Pierre Trudeau Liberal 1980–84

John Turner Liberal 1984

Brian Mulroney Progressive Conservative 1984–93

Kim Campbell Progressive Conservative 1993

Jean Chretien Liberal 1993–2003

Paul Martin Liberal 2003–06

Stephen Harper Conservative 2006–

26 Canada BRITANNICA STUDENT ENCYCLOPEDIA

Canada Day

Canada Day is the national holiday of

Canada. It is celebrated on July 1. On

that day in 1867 Canada became a

country.

In 1867 four of Great Britain’s North

American colonies joined together as a

new country. It was called the Dominion

of Canada. In 1879 a law made July

1 a holiday called Dominion Day.

Canada gained complete independence

from Great Britain in 1982. In the same

year Canada changed the holiday’s name

to Canada Day.

Canadians celebrate Canada Day with

parades, barbecues, picnics, and displays

of fireworks. They also sing the national

anthem, “O Canada.” The most important

celebration takes place in the area of

Parliament Hill, in Canada’s capital city

of Ottawa. Members of Canada’s

national police force, the Royal Canadian

Mounted Police, do horse riding

tricks. Part of the Royal Canadian Air

Force puts on an air show.

#More to explore

Canada • Ottawa

Canal

Canals are waterways that are built by

people and used for shipping, travel, and

irrigation. Canals have been an important

way to move goods and carry

people for more than 5,000 years.

Some canals make it possible for boats

to travel inland from oceans and lakes. A

canal may also serve as a shortcut

between two bodies of water. Other

canals carry drinking water to cities or

irrigation water to farms.

Building a Canal

To make a canal, builders dig a long

channel in the ground and fill it with

water. The water usually comes from a

connecting river, lake, or ocean. Builders

often line the canal with stone, concrete,

or steel to make it stronger. The lining

also prevents the water from leaking out.

Locks

Locks are an important part of many

canals, especially in areas where the land

is not completely flat. A lock is a stretch

of canal blocked off at each end by

strong gates. These gates can be opened

or closed to allow water to fill or to

drain from the lock.

Locks allow boats to travel between

lower and higher areas of a canal. When

Three young people celebrate Canada Day,

the national holiday of Canada.

The Saint

Lawrence

Seaway in

North

America

includes several

canals.

They were

built to open

the Great

Lakes to

oceangoing

ships.

BRITANNICA STUDENT ENCYCLOPEDIA Canal 27

a boat enters a lock, the gates close

behind it.Water then fills or empties

from the lock through small openings

called sluice gates. When the water in

the lock reaches the level of the next part

of the canal, the gates in front of the

boat open. The boat then passes out of

the lock.

Famous Canals

The world’s oldest canal still being used

today is the Grand Canal in China. It is

also the world’s longest canal, with a

length of about 1,085 miles (1,747 kilometers).

The Erie Canal connects the Hudson

River in New York with the eastern

shore of Lake Erie, near Buffalo, New

York. The Erie Canal was an important

shipping route in the 1800s.

The Suez Canal in Egypt connects the

Mediterranean Sea with the Red Sea.

This major shipping canal is the shortest

water route between Europe and the

Indian Ocean.

The Panama Canal is an important

shortcut between the Atlantic and

Pacific oceans. Before this canal was

built, ships had to travel around the tip

of South America to get from one ocean

to another.

In Venice, Italy, people use canals as

roadways. In the oldest parts of the city,

people travel by special boats called gondolas

instead of cars. A gondola is

pushed with a long pole.

#More to explore

Erie Canal • Irrigation • Panama Canal

• Suez Canal

Canary

The canary is a small bird known for its

singing. Canaries are found wild in the

Canary, Azores, and Madeira islands off

the coast of northwestern Africa. Hundreds

of years ago people caught these

wild birds and began breeding them.

In Venice, Italy, people travel on canals

instead of roads.

Locks allow boats to travel between lower

and higher areas of a canal.

28 Canary BRITANNICA STUDENT ENCYCLOPEDIA

Over time they have bred hundreds of

different kinds of canaries that are sold

as pets.

Several other small songbirds, such as

the American goldfinch, are sometimes

called wild canaries. But they are different

types of birds. The canary is a species,

or type, of songbird that is closely

related to goldfinches, siskins, and redpolls.

It is also related to other finches,

cardinals, and sparrows.

In the wild, canaries measure about 5.5

inches (14 centimeters) in length. They

are dull greenish brown with yellowish

breasts. Pet canaries differ in size, form,

feather color, and song. Breeders work to

develop different characteristics in the

different kinds of pet canaries. Many pet

canaries have bright yellow feathers.

Canaries have short, cone-shaped bills.

They use their bills to crack open seeds

to get at the parts that are good to eat.

They may also eat fruits.

..More to explore

Cardinal • Pet • Songbird • Sparrow

Canberra

Population

(2006

estimate), urban

area, 328,441

Canberra is the capital of the country of

Australia. The city is also the center of a

district called the Australian Capital

Territory. Canberra lies at the foot of the

Australian Alps mountain range. The

Molonglo River flows through the city.

Many people in Canberra work for the

Australian government or in tourism.

Native Australians, called Aborigines,

have lived in the Canberra region for

thousands of years. Europeans founded a

settlement there in the 1820s. The government

selected Canberra to be the

new capital of Australia in 1908. A competition

was held to choose the design

for the new city. The American architect

Walter Burley Griffin created the winning

design. Canberra officially became

the capital in 1927.Wildfires damaged

the city in 2003.

..More to explore

Australia

The Australian Parliament House is built into

a hill.

The canary is one of the most popular pet

songbirds in the world.

BRITANNICA STUDENT ENCYCLOPEDIA Canberra 29

Cancer

Cancer is a disease that causes certain

cells in the body to grow out of control.

The human body contains billions of

cells. Most of these cells reproduce, or

duplicate themselves, over and over. The

body normally controls this process. In

some people, however, certain cells start

to multiply too much. These cells are

not normal. They produce clumps of

tissue called tumors.

Some tumors are harmless, but others

are very serious. They can destroy

nearby healthy cells and organs. These

destructive tumors are called cancer.

Cells from these tumors sometimes

spread to other parts of the body and

form more tumors.

There are many different kinds of cancer.

The kind of cancer a person has

depends on where it starts to grow. It

also depends on what causes it and how

fast it grows.

Symptoms

There are some general symptoms, or

signs, that may mean a person has cancer.

These symptoms include pain,

weight loss that cannot be explained,

fever, tiredness, and changes in the skin.

Each kind of cancer also produces specific

symptoms. For example, a cough

that will not go away could be a sign of

lung cancer.

Causes

Scientists do not know why some cells

multiply too quickly. However, they

have discovered many things that can

lead to cancer. Most cancers are caused

by conditions outside the body. For

example, getting too much sunlight can

cause skin cancer. Smoking tobacco can

cause lung or mouth cancer.

As a tumor grows larger, it invades the

healthy tissues nearby. Cancer spreads when

cells from a tumor travel to other parts of the

body.

30 Cancer BRITANNICA STUDENT ENCYCLOPEDIA

In addition, eating unhealthy foods and

not exercising enough can lead to cancer.

People have a higher chance of getting

some kinds of cancer if members of

their families had them. A few viruses

also cause cancer.

Prevention

The easiest way to prevent cancer is to

stay away from the things that might

cause it. For example, doctors suggest

that people wear sunscreen lotion when